Avialae Gauthier, 1986
Definition- (Passer domesticus <- Deinonychus antirrhopus) (modified from Padian, 2004; modified from Gauthier, 1986)
Other definitions- (Archaeopteryx lithographica + Vultur gryphus) (modified from Gauthier and Wagner, 2001)
(feathered wings homologous with Vultur gryphus and used for powered flight) (Gauthier and de Queiroz, 2001)
(Passer domesticus <- Dromaeosaurus albertensis, Troodon formosus) (Maryanska et al., 2002)
(Vultur gryphus <- Deinonychus antirrhopus) (Zhang, Zhou, Xu, Wang and Sullivan, 2008)
(Passer domesticus <- Deinonychus antirrhopus, Troodon formosus) (modified from Hu, Hou, Zhang and Xu, 2009)
= Unenlagiinae Bonaparte, 1999 sensu Makovicky, Apesteguia and Agnolin, 2005
Definition- (Unenlagia comahuensis <- Velociraptor mongoliensis)
= Avialae sensu Maryanska et al., 2002
Definition- (Passer domesticus <- Dromaeosaurus albertensis, Troodon formosus)
= Avialae sensu Zhang, Zhou, Xu, Wang and Sullivan, 2008
Definition- (Vultur gryphus <- Deinonychus antirrhopus)
= Avialae sensu Hu, Hou, Zhang and Xu, 2009
Definition- (Passer domesticus <- Deinonychus antirrhopus, Troodon formosus)

Scansoriopterygidae Czerkas and Yuan, 2002
Definition- (modified from Zhang et al., 2008) (Epidexipteryx hui + Epidendrosaurus ningchengensis)
Diagnosis- (after Zhang et al., 2008) dentary toothed only anteriorly; pubic peduncle of ilium subequal in size to ischial peduncle; pubis propubic; pubic boot absent; ischium longer than pubis; ischial shaft curved dorsally; ischium distally wide.
Comments- These may be non-eumaniraptoran paravians.

Epidexipteryx Zhang, Zhou, Xu, Wang and Sullivan, 2008
E. hui Zhang, Zhou, Xu, Wang and Sullivan, 2008
Bathonian, Middle Jurassic
Daohugou Formation, Nei Mongol, China
Holotype- (IVPP V15471) (164 g; subadult) skull (43 mm), mandibles (39.3 mm), seven cervical vertebrae, cervical ribs, fourteen dorsal vertebrae, twelve dorsal ribs, gastralia, sacrum, sixteen caudal vertebrae, scapulae (31 mm), coracoids (12.2 mm), sternal plates, humeri (50 mm), radii (one proximal; 39.2 mm), ulnae (one proximal; 42 mm), metacarpal I (5.1 mm), metacarpal II (13 mm), phalanx II-1 (7.6 mm), phalanx II-2 (12.4 mm), manual ungual II (10.2 mm), metacarpal III (13.4 mm), phalanx III-2 (14 mm), phalanx III-3 (13.5 mm), manual ungual III (10 mm), ilia (34.2 mm), pubes (27.8 mm), ischia (36.2 mm), femora (51 mm), tibiae (63 mm), fibulae (59 mm), astragalocalcaneum (7 mm wide), distal tarsal III, distal tarsal IV, metatarsal I, incomplete metatarsal II, incomplete metatarsal III (31 mm), incomplete metatarsal IV, feathers
Comments- This specimen was first mentioned by Xu (2000) as a new maniraptoran similar to birds, but also to therizinosaurs, oviraptorosaurs and troodontids. It was later named and described by Zhang et al. (2008), though the manuscript was accidentally leaked September 24th to Nature Precedings, while the final version wasn't published until October 23rd. The extremely short tail compared to Scansoriopteryx may be an ontogenetic feature, as other avialans such as Confuciusornis (= Zhongornis?) and enantiornithines reduce their tail length with age. Thus it may be an older individual of Scansoriopteryx, since it is from the same formation. The metacarpals and manual phalanges were left unidentified in the paper, but are here tentatively assigned positions based on their lengths, as compared to Scansoriopteryx.
References- Xu, 2000. A new feathered maniraptoran dinosaur. The Florida Symposium on Dinosaur Bird Evolution. Publications in Paleontology No.2, Graves Museum of Archaeology and Natural History. p 27.
Zhang, Zhou, Xu, Wang and Sullivan, 2008. A bizarre Jurassic maniraptoran from China with elongate ribbon-like feathers. Nature. 455, 1105-1108.

Scansoriopteryx Czerkas and Yuan, 2002
= Epidendrosaurus Zhang, Zhou, Xu and Wang, 2002
S. heilmanni Czerkas and Yuan, 2002
= Epidendrosaurus ningchengensis Zhang, Zhou, Xu and Wang, 2002
Middle Jurassic (?)
Daohugou Formation(?), Liaoning, China
Holotype- (CAGS02-IG-gausa-1/DM 607) (130 mm, ~6 g; juvenile) posterior skull, sclerotic rings, posterior mandibles, hyoids, seven dorsal vertebrae, dorsal rib fragments, gastralia, sacrum, twenty-two caudal vertebrae, fourteen chevrons, distal scapula, coracoid, partial furcula, humerus (18.5 mm), radii (one distal; 14.75 mm), ulnae (one distal; 15 mm), distal carpals I, metacarpals I (2.1 mm), phalanges I-1 (5 mm), manual unguals I (3 mm), metacarpals II (5.5 mm), phalanges II-1 (3.1 mm), phalanges II-2 (5.2 mm), manual unguals II (3 mm), metacarpals III (5.75 mm), phalanges III-1 (7.1 mm), phalanges III-2 (6.5 mm), phalanges III-3 (6 mm), manual ungual III (2.8 mm), ilia (11.5 mm), distal pubes (9 mm), ischia (11.5 mm), femora (16.5 mm), tibiae (one distal; 19.25 mm), (?)fibulae (one distal), astragali, calcaneum, distal tarsal III, distal tarsal IV, metatarsal I, phalanx I-1 (2.75 mm), pedal ungual I (1.9 mm), metatarsals II, phalanx II-1 (2.75 mm), phalanx II-2 (2.8 mm), pedal ungual II (2.5 mm), metatarsals III (12 mm), phalanx III-1 (2.5 mm), phalanx III-2 (2 mm), phalanx III-3 (2.5 mm), pedal ungual III (2 mm), metatarsals IV, phalanx IV-1 (2 mm), phalanx IV-2 (1.25 mm), phalanx IV-3 (1.1 mm), phalanx IV-4 (2 mm), pedal ungual IV (2 mm), metatarsal V, feathers, scales
Bathonian, Middle Jurassic
Daohugou Formation, Nei Mongol, China
Referred- (IVPP V12653; holotype of Epidendrosaurus ningchengensis) (130 mm, ~6 g; juvenile) frontals (7.8 mm), parietals (5.3 mm), sclerotic ring, mandibles (18 mm), nine cervical vertebrae, cervical rib, four dorsal vertebrae, five dorsal ribs, ten caudal vertebrae, caudal impression, several chevrons, scapulae (11.3 mm), coracoid, humeri (17.1 mm), radius (15 mm), ulna (15 mm), distal phalanx I-1, manual ungual I (4.1 mm), metacarpal II (5.2 mm), phalanx II-1 (3.2 mm), phalanx II-2 (5.4 mm), manual ungual II (3.2 mm), metacarpal III (5.8 mm), phalanges III-1 (7.3 mm), phalanges III-2 (6.8 mm), phalanges III-3 (6.3 mm), manual ungual III (2.9 mm), femora (one distal; 16.2 mm), tibiae (18.9 mm), fibulae, astragalus, metatarsals I, phalanges I-1, pedal unguals I, metatarsals II, phalanges II-1, phalanges II-2, pedal ungual II, metatarsals III (11.9 mm), phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, metatarsals IV, phalanges IV-1, phalanges IV-2, phalanx IV-3, phalanges IV-4, pedal unguals IV, feathers (Zhang , Zhou, Xu and Wang, 2002)
Comments- Scansoriopteryx and Epidendrosaurus appear to be synonymous, but there are complications in deciding which name has priority. The description Epidendrosaurus was submitted June 10th, 2002, published online on August 21st, but not published in print until September 30th. The description of Scansoriopteryx is dated August 1st, 2002, but was not distributed until around September 2nd. Indeed, Zhang (DML, 2002) stated he received faxed copies of the paper from Czerkas on August 26th-29th which still lacked page numbers. Zhang (DML, 2002) also cited a Naturwissenschaften editor as claiming that nomenclatural acts published in Springer Verlag journals (including Naturwissenschaften) are valid at the date of their online publication as long as a print version follows. Harris (2004) has formally recommended such an amendment to articles 8.1.3 and 9.8 of the ICZN, but this has not been adopted by the ICZN as of this time. Thus online publication dates do not count even if followed by a print version, regardless of the presence of a Digital Object Identifier (DOI) code to ensure citability. This makes Scansoriopteryx the valid name, as it was published in print almost a month prior to Epidendrosaurus. Yet if Harris' suggestions are incorporated into the ICZN, they may be retroactive and thus favor Epidendrosaurus, as the online version of its description was distributed prior to the time it can be proven Scansoriopteryx's description was.
Czerkas and Yuan (2002) stated Scansoriopteryx's holotype derived from the Dawangzhangzi Beds of the Yixian Formation (Early Aptian, Early Cretaceous), but Wang et al. (2005) suggested it was probably from the Daohugou Formation instead. Czerkas has apparently revised his opinion since 2004 at least and now believes the latter as well. While Zhang (DML, 2002) implied it had been smuggled into the US, Ford (DML, 2002) stated personal communication with Czerkas revealed that he has been loaned the specimen from a Chinese Museum (presumably CAGS) through a middleman. Regardless, it does seem there is little original stratigraphic information on the specimen, and it is here referred to the Daohugou Formation only tentatively.
Czerkas and Yuan's description of Scansoriopteryx is fraught with errors symptomatic of those who place maniraptorans outside Theropoda. They believe theropods are defined by being terrestrial and having a third manual digit shorter than the second digit, though dinosaur workers near universally define it phylogenetically instead (generally as those taxa closer to birds than to sauropods, though more recently using Allosaurus as the internal specifier instead of a bird). The authors also confusingly classify Scansoriopteryx as a maniraptoran and a saurischian, but exclude it from Theropoda and more tentatively, Dinosauria. This is not possible given the phylogenetic definitions of these clades, as theropods must be saurischians (Saurischia is defined as including a theropod) and saurischians must be dinosaurs (Dinosauria is defined as including a saurischian). The exact phylogeny Czerkas advocates is uncertain, since he never states explicitly where sauropodomorphs or ornithischians go, though he seems to have these groups and theropods branching off (para- or monophyletically?) before Scansoriopteryx, which is itself outside a clade containing deinonychosaurs, oviraptorosaurs and birds. Czerkas and Yuan state there are "massive reversals secondarily resembling primitive characteristics" that would have to take place if Scansoriopteryx were a theropod. The few that are listed are either also present in some other maniraptoriforms (broad sacral vertebrae; metacarpal III longer than II; manual phalanx III-3 shorter than III-1 and III-2; partially closed acetabulum; narrow pubic peduncle on ilium), or misinterpreted (unfused clavicles; robust fibula), except for the short pubis. Notably the ischium also differs from most theropods in lacking an obturator notch, though this is not commented on by the authors. In any case, Czerkas' phylogeny has received no support from phylogenetic analysis, and Scansoriopteryx has been universally recovered as a paravian theropod, generally a basal avialan.
References- Czerkas, 2000. An arboreal theropod. The Florida Symposium on Dinosaur Bird Evolution. Publications in Paleontology No.2, Graves Museum of Archaeology and Natural History. p 14.
Czerkas and Yuan, 2002. An arboreal maniraptoran from Northeast China. Feathered Dinosaurs and the Origin of Flight. The Dinosaur Museum Journal. 1, 63-95.
Zhang , Zhou, Xu and Wang, 2002. A juvenile coelurosaurian theropod from China indicates arboreal habits. Naturwissenschaften. 89, 394-398.
http://dml.cmnh.org/2002Sep/msg00673.html
http://dml.cmnh.org/2002Sep/msg00704.html
Harris, 2004. Published works" in the Electronic Age: Recommended amendments to Articles 8 and 9 of the Code. Bulletin of Zoological Nomenclature. 61(3), 138-148.
http://dml.cmnh.org/2004Apr/msg00048.html
Wang, Zhou, He, Jin, Wang, Zhang, Wang, Xu and Zhang, 2005. Stratigraphy and age of the Daohugou Bed in Ningcheng, Inner Mongolia. Chinese Science Bulletin. 50(20), 2369-2376.

unnamed clade (Anchiornis huxleyi + Passer domesticus)

Anchiornis Xu, Zhao, Norell, Sullivan, Hone, Erickson, Wang, Han and Guo, 2008
A. huxleyi Xu, Zhao, Norell, Sullivan, Hone, Erickson, Wang, Han and Guo, 2008
Oxfordian, Late Jurassic
Tiaojishan Formation, Liaoning, China
Holotype- (IVPP V14378) (~340 mm; 110 g; subadult or young adult) posterior cervical vertebrae (eighth cervical 5 mm), thirteen dorsal vertebrae (second dorsal 4.3 mm, seventh dorsal 4.8 mm, eleventh dorsal 5.1 mm), nineteen dorsal ribs, sacrum, seventeen caudal vertebrae (first caudal 2.8 mm, tenth caudal 7.4 mm), chevrons, scapulae (26.8 mm), coracoids, furcula, humeri (41.5 mm), radius, ulna (37.1 mm), radiale, (?)ulnare, metacarpal I, carpometacarpus, phalanx I-1, manual ungual I, phalanx II-1, phalanx II-2, manual ungual II, phalanx III-1, phalanx III-2, phalanx III-3, manual ungual III, incomplete ilium (~26.2 mm), partial ischium, femora (43.2 mm), tibiae (67.8 mm), metatarsal I, metatarsals II, phalanges II-1, phalanges II-2, pedal unguals II, metatarsals III, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, metatarsals IV, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, metatarsals V, ungual sheaths, feathers
Referred- (LPM-B00169) skull (63.7 mm), mandibles (53.8 mm), eight cervical vertebrae (series 66.8 mm), thirteen dorsal vertebrae (series 85.4 mm), sixteen dorsal ribs, gastralia, sacrum (31 mm), nineteen caudal vertebrae (first caudal 5.2 mm, thirteenth caudal 14.2 mm, eighteenth caudal 13.5 mm), seventeen chevrons, scapulae (one fragmentary; 45.2 mm) coracoid, furcula, humeri (69 mm), radii (54 mm), ulnae (55.1 mm), radiales, ulnares, semilunate carpals, metacarpals I (12.4 mm), phalanges I-1 (26.2 mm), manual ungual I (15.6 mm), metacarpals II (33.9 mm), phalanges II-1 (21 mm), phalanges II-2 (27 mm), manual unguals II (20.2 mm), metacarpals III (30.5 mm), phalanges III-1 (7.2 mm), phalanges III-2 (8.1 mm), phalanx III-3 (14.2 mm), manual ungual III (13.8 mm), manual claw sheaths, ilia (one partial; 37.4 mm), pubes (61.4 mm), ischium (22.4 mm), femora (66.2 mm), tibiae (106.4 mm), fibula, astragalus, distal tarsal IV, metatarsals I (11.1 mm), pedal ungual I, metatarsals II (51.2 mm), phalanges II-1 (11.5 mm), phalanges II-2 (12.2 mm), pedal unguals II (14.9 mm), metatarsals III (55.2 mm), phalanges III-1 (12.9 mm), phalanges III-2 (11.1 mm), phalanges III-3 (10.5 mm), pedal unguals III (13.7 mm), metatarsals IV (51.9 mm), phalanges IV-1 (10.8 mm), phalanges IV-2 (8.8 mm), phalanges IV-3 (7 mm), phalanges IV-4 (7.6 mm), pedal unguals IV (13.5 mm), metatarsals V (19.2 mm), pedal claw sheaths, body feathers, remiges, metatarsal remiges (Hu et al., 2009)
specimen (Hu et al., 2009)
Diagnosis- (after Xu et al., 2008) ventral surface of coracoid sculptured by numerous small pits; extremely short ischium (less than one-fourth of the femoral length).
(after Hu et al., 2009) elongate tibia (157-161% of femoral length).
Comments- While Xu et al. (2008) used a version of the Theropod Working Group matrix with added characters from Xu's thesis to place Anchiornis as an avial more basal than Archaeopteryx, Hu et al. (2009) used Senter's modified version of the TWG matrix to place it as a troodontid more derived than Sinovenator but less so than Mei and other taxa. Each includes relevent taxa and characters missing from the other. Preliminary combination of datasets suggests either possibility is equally likely and Anchiornis might be best placed as Paraves incertae sedis.
References- Xu, Zhao, Norell, Sullivan, Hone, Erickson, Wang, Han and Guo, 2008. A new feathered maniraptoran dinosaur fossil that fills a morphological gap in avian origin. Chinese Science Bulletin. 54(3), 430-435.
Hu, Hou, Zhang and Xu, 2009. A pre-Archaeopteryx troodontid theropod from China with long feathers on the metatarsus. Nature. 461, 640-643.

undescribed avialian (Janensch 1914)
Tithonian, Late Jurassic
Upper Dinosaur Member of the Tendaguru Formation, Tanzania
Material- metacarpal II (27.3), metacarpal III (24.5 mm)
Comments- This specimen was discovered in 1910 associated with a Dicraeosaurus skeleton, initially briefly described by Janensch (1914), then illustrated and described by Stremme (1916-1919). Lambrecht (1933) quotes Stremme as saying the elements as fused proximally, with free joints distally for the articulation of phalanges. Stremme furthermore noted metacarpal III is more slender than II as in birds, and that the carpometacarpal fusion is similar to birds except for the basal Archaeopteryx. Lambrecht thus dismisses later opinions (Arldt, 1922; Parkinson, 1930) that stated Stremme considered it a relative of Archaeopteryx. His own opinion was that the carpometacarpus resembled Rhea, so might indicate ratite relationships. The fusion of metacarpals II and III is characteristic of ornithurines (sensu Gauthier), but also known in Anchiornis and a few less birdlike taxa (Mapusaurus, Therizinosaurus, Heyuannia).
References- Janensch, 1914. Ubersicht uber die Wirbeltierfauna der Tendaguru-Schichten. Archiv fur Biontologie. 3, 81-110.
Stremme, 1916-1919. Uber die durch Bandverknocherung hervorgerufene proximale Verschmelzung zweier Mittelhand - oder Mittelfussknochen eines Reptils. Wissenschaftliche Ergebnisse der Tendaguru-Expedition. Archiv fur Biontologie. 4, 143-144.
Arldt, 1922. Handbuch der Palaeogeographie. Volume 2.
Parkinson, 1930. The dinosaur in East Africa: An account of the giant reptile beds of Tendaguru, Tanganyika territory. London.
Lambrecht, 1933. Handbuch der Palaeornithologie. Gebruder Borntraeger, Berlin. 1022 pp.

Aves sensu Chiappe, 1992
Definition- (Archaeopteryx lithographica + Passer domesticus)
= Avialae sensu Gauthier and Wagner, 2001
Definition- (Archaeopteryx lithographica + Vultur gryphus)

unnamed avialan (Seeley, 1869)
Late Albian, Early Cretaceous
Cambridge Greensand, England
Material- ?(BGS 87931) (juvenile) first sacral vertebra (8.5 mm) (Galton and Martin, 2002b)
?(BGS 87933) proximal femur (Galton and Martin, 2002b)
(SMC B55274) dorsal vertebra (7.4 mm) (Seeley, 1869)
(SMC B55278) dorsal vertebra (10.1 mm) (Seeley, 1869)
(SMC B55280) dorsal vertebra (8.5 mm) (Seeley, 1869)
?(SMC B55328) proximal coracoid (Seeley, 1869)
(YORYMG 584) posterior cervical vertebra (9.3 mm) (Seeley, 1876)
Comments- SMC B55274, 55278 and 55280 are three of the four dorsal vertebrae listed as "Enaliornis" by Seeley (1869). SMC B55274 (mistyped B55279 in the figures of Galton and Martin, 2002b) and B55280 are dorsal vertebrae referred to Enaliornis sedgwicki by Seeley (1876), while YORYMG 584 was identified as an Enaliornis dorsal vertebra by Seeley. As they differ from hesperornithines, they were placed in Avialae incertae sedis by Galton and Martin (2002a, b) along with SMC B55278. Galton and Martin (2002b) tentatively referred the sacral vertebra BGS 87931 and proximal femur BGS 87933 to the same taxon. SMC B55328 was stated to be a proximal coracoid by Seeley (1869), and while possibly true, Galton and Martin (2002b) exclude it from Hesperornithes. This will be redescribed by Galton (in prep.). Galton et al. (2009) refer it all of this material to Aves indet..
References- Seeley, 1869. Index to the fossil remains of Aves, Ornithosauria and Reptilia, from the Secondary System of strata arranged in the Woodwardian Museum of the University of Cambridge. Deighton, Bell & Co.,
Cambridge. 143 pp.
Seeley, 1876. On the British fossil Cretaceous birds. Quarterly Journal of the Geological Society of London. 32, 496-515.
Galton and Martin, 2002a. Enaliornis, an Early Cretaceous hesperornithiform bird from England, with comments on other Hesperornithiformes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 317-338.
Galton and Martin, 2002b. Postcranial anatomy and systematics of Enaliornis Seeley, 1876, a footpropelled diving bird (Aves: Ornithurae: Hesperornithiformes) from the Early Cretaceous of England. Revue de Paleobiologie. 21(2), 489-538.
Galton, Dyke and Kurochkin, 2009. Re-analysis of Lower Cretaceous fossil birds from the UK reveals an unexpected diversity. Journal of Vertebrate Paleontology. 29(3), 102A.
Galton, in prep. Additional bird bones (Hesperornithiformes Enaliornis and Aves incertae sedis) from the Early Cretaceous of England. Revue Paleobiologie.

undescribed avialaen (Vidal, 1902)
Late Berriasian-Early Barremian, Early Cretaceous
La Pedrera de Rubies Lithographic Limestones Formation, Spain
Material- (destroyed) skeleton
Comments- Vidal (1902) mentioned the accidental destruction of a fossil bird, which based on provenence may belong to Noguerornis or the unnamed La Pedrera juvenile enantiornithine taxon.
Reference- Vidal, 1902. Sobre la presencia del tramo Kimeridgense del Montsech y hallazgo de un batracio en sus hiladas. Memorias de la Real Academia de Ciencias y Artes de Barcelona. 4(18), 263-267.

unnamed possible avialan (Zernezky, 1958)
Early Cretaceous
Tete-Oba, Ukraine
Material- hindlimb (pedal digit III 50 mm)
Comments- Zernezky (1958) described this as a bird with narrow pedal digits and a very short hallux. He considered it to have ralliform affinities, but it has not been studied subsequently
Reference- Zernezky, 1958. Enigmatic imprint. Nature (Moscow). 4, 113, [in Russian]

unnamed possible Avialae (Kessler, 1984)
Late Berriasian-Early Valanginian, Early Cretaceous
Cornet bauxite, Bihor, Romania
Material- ?(MTCO-P 1912) distal ulna
?(MTCO coll.) distal humerus
?(MTCO coll.) about fifty-three elements
Comments- Kessler (1984) noted approximately sixty bird-like fragments from the Cornet bauxite, six of which can "with certainty be attributed to birds." These presumably include the holotypes of Eurolimnornis corneti (MTCO-P 7896; distal humerus) and Palaeocursornis corneti (MTCO-P 1637; distal femur), as well as an incomplete humerus initially referred to Archaeopteryx sp. (MTCO-P 1503; currently Maniraptora indet.), two specimens questionably referred to Eurolimnornis (MTCO-P 207 a distal carpometacarpus and MTCO-P 6966 an ulnar fragment). Jurcsak and Kessler (1991) also illustrate a distal ulna (MTCO-P 1912) and distal humerus referred to birds. Benton et al. (1997) note that none of the material was found associated and state some could be pterosaurian or theropod instead. Galton et al. (2009) indicate some elements are hesperornithine and closely resembles Enaliornis. They are being redescribed by Benton and Unwin (in prep.).
References- Kessler, 1984. Lower Cretaceous birds from Cornet, Roumania. In Rief and Westphal (eds). Third Symposium on Mesozoic Terrestrial Ecosystems, Tubingen. 119-121.
Jurcsack and Kessler, 1991. The Lower Cretaceous paleofauna from Cornet, Bihor County, Romania. Nymphaea. 21, 5-32.
Benton, Cook, Grigorescu, Popa and Tallodi, 1997. Dinosaurs and other tetrapods in an Early Cretaceous bauxite-filled fissure, northwestern Romania. Palaeogeography, Palaeoclimatology, Palaeoecology. 130(1-4), 275-292.
Hope, 2002. The Mesozoic radiation of Neornithes. In Chiappe and Witmer (eds). Mesozoic birds: Above the heads of dinosaurs. Berkeley: University of California Press. 339-388.
Galton, Dyke and Kurochkin, 2009. Re-analysis of Lower Cretaceous fossil birds from the UK reveals an unexpected diversity. Journal of Vertebrate Paleontology. 29(3), 102A.

undescribed Avialae (Kirkland et al., 1997)
Late Albian, Early Cretaceous
Mussentuchit Member of the Cedar Mountain Formation, Utah, US
Material- teeth
Comments- Kirkland et al. (1997) listed Aves order indet., while Cifelli et al. (1999) noted two Avialae dental morphs, one referrable to Hesperornithes and one not.
References- Kirkland, Britt, Burge, Carpenter, Cifelli, DeCourten, Eaton, Hasiotis and Lawton, 1997. Lower to Middle Cretaceous dinosaur faunas of the Central Colorado Plateau: a key to understanding 35 million years of tectonics, sedimentology, evolution, and biogeography. Brigham Young University Geology Studies. 42, 69-103.
Cifelli, Nydam, Gardner, Weil, Eaton, Kirkland, Madsen, 1999. Medial Cretaceous vertebrates from the Cedar Mountain Formation, Emery County, Utah: the Mussentuchit Local Fauna. in Gillette (ed.). Vertebrate Paleontology in Utah. Utah Geological Survey, Miscellaneous Publication. 99-1, 219-242.

undescribed Avialae (Tokaryk, Cumbaa and Storer, 1997)
Middle Cenomanian, Late Cretaceous
Belle Fourche Member of the Ashville Formation, Saskatchewan, Canada
Material- (SMNH coll.) four fused synsacral vertebrae, several coracoids, proximal carpometacarpus, three pelvic elements, many fragments (Tokaryk et al., 1997)
many elements (Cumbaa et al., 2006)
Comments- Tokaryk et al. (1997) note many unidentified bird elements, including three pelvic elements which may belong to Pasquiaornis. Cumbaa et al. (2006) mention numerous bird remains from the Bainbridge River Bonebed, some of which are probably not Pasquiaornis.
References- Tokaryk, Cumbaa and Storer, 1997. Early Late Cretaceous birds from Saskatchewan, Canada: the oldest diverse avifauna known from North America. Journal of Vertebrate Paleontology. 17(1), 172-176.
Cumbaa, Schröder-Adams, Day and Phillips, 2006. Cenomanian bonebed faunas from the northeastern margin, Western Interior Seaway. In Lucas and Sullivan (eds). Late Cretaceous Vertebrates from the Western Interior. New Mexico Museum of Natural History and Science Bulletin. 35, 139-155.

unnamed possible avialan (Molnar, 1999)
Albian, Early Cretaceous
Griman Creek Formation, New South Wales, Australia
Material- (AM F103590) proximal tibiotarsus (5.9x4.6 mm)
Comments- This specimen is less derived than ornithuromorphs except for Patagopteryx in lacking a medial cnemial crest. The proximal surface is not round, unlike most enantiornithines. Molnar excluded non-bird theropods based on the lack of cnemial crest curvature and poorly developed condyles. Unfortunately, good comparative material for basal birds is lacking.
Reference- Molnar, 1999. Avian tibiotarsi from the Early Cretaceous of Lightning Ridge, N.S.W. In Tomida, Rich and Rich (eds). Proceedings of the Second Gondwanan Dinosaur Symposium, National Sciences Museum Monographs. 15, 197-209.

Avialae indet. (Sankey and Brinkman, 2000)
Late Campanian, Late Cretaceous
Judith River Group, Alberta, Canada
Material- ?(RTMP 84.92.205) tooth (2.7 mm) (Sankey et al., 2002)
?(RTMP 86.21.68) tooth (3.7 mm) (Sankey et al., 2002)
(RTMP 86.45.27) tooth (3.7 mm) (Sankey et al., 2002)
(RTMP 86.52.54) tooth (4.7 mm) (Sankey et al., 2002)
(RTMP 86.172.53) tooth (2.9 mm) (Sankey et al., 2002)
(RTMP 87.4.19) tooth (5.5 mm) (Sankey et al., 2002)
(RTMP 87.4.46) tooth (3.6 mm) (Sankey et al., 2002)
(RTMP 87.20.8) tooth (4.3 mm) (Sankey et al., 2002)
(RTMP 87.30.10) tooth (~3.7 mm) (Sankey et al., 2002)
?(RTMP 87.158.76) tooth (3.3 mm) (Sankey et al., 2002)
(RTMP 87.158.77) tooth (3.1 mm) (Sankey et al., 2002)
(RTMP 88.11.65) tooth (2.9 mm) (Sankey et al., 2002)
?(RTMP 89.103.25) tooth (5.4 mm) (Sankey et al., 2002)
(RTMP 95.145.34a) tooth (2.1 mm) (Sankey et al., 2002)
(RTMP 95.145.34b) tooth (4 mm) (Sankey et al., 2002)
(RTMP 95.145.34c) tooth (3.5 mm) (Sankey et al., 2002)
(RTMP 95.147.30) tooth (2.4 mm) (Sankey et al., 2002)
(RTMP 95.151.21) tooth (2.3 mm) (Sankey et al., 2002)
?(RTMP 95.174.52) tooth (2.3 mm) (Sankey et al., 2002)
?(RTMP 95.177.79) tooth (3 mm) (Sankey et al., 2002)
(RTMP 95.180.49) tooth (3.2 mm) (Sankey et al., 2002)
(RTMP 95.181.10a) tooth (3.1 mm) (Sankey et al., 2002)
(RTMP 95.181.10b) tooth (3.3 mm) (Sankey et al., 2002)
?(RTMP 95.181.10c) tooth (3.3 mm) (Sankey et al., 2002)
(RTMP 95.181.10d) tooth (3.3 mm) (Sankey et al., 2002)
?(RTMP 95.181.60e) tooth (2.4 mm) (Sankey et al., 2002)
?(RTMP 95.181.60f) tooth (2.5 mm) (Sankey et al., 2002)
(RTMP 96.62.51) tooth (3.2 mm) (Sankey et al., 2002)
(RTMP 96.62.62) tooth (3.5 mm) (Sankey et al., 2002)
(RTMP 96.62.62a) tooth (3.8 mm) (Sankey et al., 2002)
(RTMP 96.62.62b) tooth (2.7 mm) (Sankey et al., 2002)
Comments- These teeth are said to resemble Hesperornis, and may belong to hesperornithines and/or enantiornithines. Several are questionably referred to birds (indicated by question marks above), since they have serrations (generally very tiny), which are unreported in bird teeth preserved in situ. They may belong to juvenile Richardoestesia instead, which the bird teeth grade into.
References- Sankey and Brinkman, 2000. New theropod and bird teeth from the Late Cretaceous (Campanian) Judith River Group, Alberta. Journal of Vertebrate Paleontology. 20(3), 67A.
Sankey, Brinkman, Guenther and Currie, 2002. Small theropod and bird teeth from the Late Cretaceous (Late Campanian) Judith River Group, Alberta. Journal of Paleontology. 76(4), 751-763.

unnamed Avialae (Osi, 2004)
Santonian, Late Cretaceous
Csehbanya Formation, Hungary
Material- (MTM V.2002.05) (juvenile) distal femur
(MTM V.2003.19) distal metatarsal III
Comments- These were briefly described as enantiornithines by Osi (2004), but later placed more generally as non-avian birds by him in 2008 when they were described in detail.
References- Osi, 2004. Enantiornithine bird remains from the Late Cretaceous of Hungary. Sixth International Meeting of the Society of Avian Palaeontology and Evolution, Abstracts. 50.
Osi, 2008. Enantiornithine bird remains from the Late Cretaceous of Hungary. Oryctos. 7, 55-60.

Archaeopterygidae Huxley, 1871
Definition- (Archaeopteryx lithographica <- Passer domesticus) (Sereno, in press)
= Sauriurae Haekel, 1866
= Saururae Huxley, 1867
= Archornithidae Carus, 1875
= Saurornithes Nicholson, 1879
= Saururi Vogt, 1879
= Ornithopappi Stejneger, 1885
= Archaeopteryges Furbringer, 1888
= Archaeopterygiformes Furbringer, 1888
= Archornithes Furbringer, 1888
= Saurura Steinmann and Doederlein, 1890
= Saurornithes Beddard, 1898
= Archornithiformes Shefeldt, 1903
= Archaeornithidae Petronievics, 1925
= Archaeopterygomorphi Hay, 1930
= Archaeopteryx sensu Sereno, 1998
Definition- (Archaeopteryx lithographica <- Passer domesticus) (modified)
Comments- Several taxa have been referred to Archaeopterygidae or Archaeopteryx itself in the past, but do not belong there. Parkinson (1930) and several other authors have alluded to an Archaeopteryx-like specimen from the Tendaguru Formation of Tanzania, but this is based on a misreading of Stremme (1916-1919), who noted the isolated carpometacarpus is unlike Archaeopteryx. It is probably avialan, but may be an ornithurine. Lambrecht (1933) cites the species Archaeopteryx "vicensensis", but this nomen nudum was later claimed to be pterosaurian (Kleinschmidt pers. comm. to Brodkorb, 1978). Jensen (1981) identified a proximal femur (BYU 2023) as Archaeopteryx, but it is also similar to basal dromaeosaurids such as Microraptor and Unenlagia. Kessler and Jurcsak (1984) described an incomplete humerus from the Early Cretaceous of Romania as Archaeopteryx sp., but it could easily belong to another small maniraptoran as well. Paul (1988) referred all dromaeosaurids to Archaeopterygidae, which has not been recovered in any phylogenetic analysis. "Proornis" was originally called "the North Korean Archaeopteryx" (e.g. anonymous, 1995), but seems to be a confuciusornithid instead. Weigert (1995) described 103 teeth from the Guimarota Formation of Portugal as cf. Archaeopteryx sp., but they are not avialan and may belong to a basal deinonychosaur instead. Protarchaeopteryx was assigned to the family by Ji and Ji (1997) and Paul (2002), but is a basal oviraptorosaur. Forster et al. (1998) found Rahonavis and Unenlagia to clade with Archaeopteryx in some most parsimonious trees, but Rahonavis has generally been found to be an ornithurine or dromaeosaurid since, while Unenlagia has been found in basal Avialae or Dromaeosauridae. Rauhut (2002) referred Paronychodon to Archaeopterygidae, but this was based on comparisons to the Guimarota teeth noted above. Ji et al. (2005) described Jinfengopteryx as being more closely related to Archaeopteryx than to Aves, but is now recognized as a basal troodontid.
Sauriurae- Sauriurae was a group first used by Haekel (1866) for Archaeopteryx, who placed Neornithes/Aves in the Ornithurae instead. This taxonomy was followed for over a century, with hesperornithines and ichthyornithines being added to Ornithurae by later authors. Martin (1983) was the first author to place enantiornithines in Sauriurae, which has been followed near universally by those who doubt the dinosaur-bird relationship. Additional taxa have also been assigned to Sauriurae including Confuciusornis (Hou et al., 1995), Sinosauropteryx (Ji and Ji, 1996), Protarchaeopteryx (Ji and Ji, 1997), Yandangornis (Cai and Zhao, 1999), Caudipteryx (Martin and Czerkas, 2000), Jeholornis (Martin, 2004), Vorona (Kurochkin, 2006), and lately all deinonychosaurs and oviraptorosaurs (Martin, 2004). The group has basically consisted of any non-ornithuromorph birds considered by the authors, with the notable exception of Kurochkin (2006), who places Protoavis and confuciusornithids in Ornithurae and views sauriurines as being theropods while ornithurines are not. While there may be some evidence for placing confuciusornithids and enantiornithines in a group exclusive of Aves, phylogenetic analyses are unanimous in rejecting a clade of Archaeopteryx and enantiornithines which excludes Aves.
References- Haekel, 1866.
Huxley, 1867.
Carus, 1875.
Nicholson, 1879.
Vogt, 1879.
Stejneger, 1885.
Furbringer, 1888. Untersuchungeb zur Morphologie und Systematik der Vogel. Amsterdam: Holkema. 1751 pp.
Steinmann and Doederlein, 1890.
Beddard, 1898.
Shufeldt, 1903. On the classification of certain groups of birds. The American Naturalist. 37, 33-64.
Stremme, 1916-1919. Uber die durch Bandverknocherung hervorgerufene proximale Verschmelzung zweier Mittelhand - oder Mittelfussknochen eines Reptils. Wissenschaftliche Ergebnisse der Tendaguru-Expedition. Archiv fur Biontologie. 4, 143-144.
Petronievics, 1925. Uber die Berliner Archaeornis. Ann. Geol. Peninsule Balkan. 8(1), 1-52.
Hay, 1930.
Parkinson, 1930. The dinosaur in East Africa: An account of the giant reptile beds of Tendaguru, Tanganyika territory. London.
Lambrecht, 1933. Handbuch der Palaeornithologie. 1024 pp.
Brodkorb, 1963. Catalogue of fossil birds. Part 1 (Archaeopterygiformes through Ardeiformes). Bull. Florida State Mus., Bioi. Sci.. 7, 179-293.
Brodkorb, 1978. Catalogue of Fossil Birds. Part 5 (Passeriformes). Bull. Florida State Mus., Biol. Sci. 23, 139-228.
Jensen, 1981. Another look at Archaeopteryx as the worlds oldest bird. Encyclia, The Journal of the Utah Academy of Sciences, Arts, and Letters. 58, 109-128.
Kessler and Jurcsák, 1984. Fossil birds remains in the bauxite from Cornet (Pa¢durea Craiului Mountains, Romania). 75 years of the Laboratory of Paleontology, University of Bucharest, Romania, Special Volume. 129-134.
Paul, 1988. Predatory Dinosaurs of the World. Simon and Schuster Co., New York. 464 pp.
Anonymous, 1994. Korean Pictorial. 1994(2).
Hou, Zhou, Gu and Zhang, 1995. Confuciusornis sanctus, a new Late Jurassic sauriurine bird from China. Chinese Science Bulletin. 40(18), 1545-1551 [in Chinese].
Weigert, 1995. Isolierte Zahne von cf. Archaeopteryx sp. aus dem Oberen Jura der Kohlengrube Guimarota (Portugal). N. Jb., Geol. Palaont. Mh. 9, 562-576.
Ji and Ji, 1996. On discovery of the earliest bird fossil in China and the origin of birds. Chinese Geology. 233, 30-33.
Ji and Ji, 1997. A Chinese archaeopterygian, Protarchaeopteryx gen. nov.. Geological Science and Technology. 238, 38-41.
Forster, Sampson, Chiappe and Krause, 1998. The theropod ancestry of birds: New evidence from the Late Cretaceous of Madagascar. Science. 279, 1915-1919.
Cai and Zhao, 1999. A long tailed bird from the Late Cretaceous of Zhejiang. Science in China (series D). 42(4), 434-441.
Martin and Czerkas, 2000. The fossil record of feather evolution in the Mesozoic. American Zoologist. 40(4), 687-694.
Paul, 2002. Dinosaurs of the Air. The Johns Hopkins University Press, Baltimore. 460 pp.
Rauhut, 2002. Dinosaur teeth from the Barremian of Una, Province of Cuenca, Spain. Cretaceous Research. 23, 255-263.
Martin, 2004. A basal archosaurian origin for birds. Acta Zoologica Sinica. 50(6), 978-990.
Ji, Ji, Lu, You, Chen, Liu and Liu, 2005. First avialan bird from China (Jinfengopteryx elegans gen. et sp. nov.). Geological Bulletin of China 24(3): 197-205.
Kurochkin, 2006. Parallel evolution of theropod dinosaurs and birds. Entomological Review. 86(suppl. 1), S45-S58.

Archaeopteryx Meyer, 1861
= Griphosaurus Wagner, 1862 (nomen rejectum)
= Griphornis Owen vide Woodward, 1862 (nomen rejectum)
= Archaeornis Petronievics vide Petroneivics and Woodward, 1917
= Jurapteryx Howgate, 1985
= Wellnhoferia Elzanowski, 2001
Other definitions- (Archaeopteryx lithographica <- Passer domesticus) (modified from Sereno, 1998)
A. lithographica Meyer, 1861
= Pterodactylus (Rhamphorhynchus) crassipes Meyer, 1857 (nomen rejectum)
= Griphornis longicaudatus Owen vide Woodward, 1862 (nomen rejectum)
= Griphosaurus problematicus Wagner vide Woodward, 1862 (nomen rejectum)
= Archaeopteryx macrura Owen, 1863 (nomen rejectum)
= Archaeopteryx siemensii Dames, 1897
= Archaeornis seimensii (Dames, 1897) Petronievics vide Petroneivics and Woodward, 1917
= Archaeopteryx oweni Petronievics, 1921
= Griphosaurus longicaudatus (Owen vide Woodward, 1862) Owen vide Brodkorb, 1963 (nomen rejectum)
= Scaphognathus crassipes (Meyer, 1857) Wellnhofer, 1970 (nomen rejectum)
= Archaeopteryx crassipes (Meyer, 1857) Ostrom, 1972
= Archaeopteryx recurva Howgate, 1984
= Jurapteryx recurva (Howgate, 1984) Howgate, 1985
= Archaeopteryx bavarica Wellnhofer, 1993
= Wellnhoferia grandis Elzanowski, 2001
Early Tithonian, Late Jurassic
Upper Solnhofen Lithographic Limestone, Germany
Holotype- ?(HMN.Ab.100; BSP coll.) secondary feather (58 mm)
Referred- (Burgermeister Muller Museum coll.; Solnhofen specimen; sixth specimen; holotype of Wellnhoferia grandis) (530 day old subadult) partial skull (~65 mm), sclerotic plates, partial mandible (~61 mm), axis, third cervical vertebra (~9 mm), partial fourth cervical vertebra, cervical ribs, partial eleventh dorsal vertebra, twelfth dorsal vertebra (~8 mm), thirteenth dorsal vertebra (~8 mm), fourteenth dorsal vertebra (8.8 mm), dorsal ribs, gastralia, (sacrum ~28 mm) partial first sacral vertebra, second sacral neural spine, third sacral neural arch, fourth sacral transverse process, fifth sacral neural arch, first caudal vertebra (5.4 mm), second caudal vertebra (6.2 mm), third caudal vertebra (6.7 mm), fourth caudal vertebra (6.5 mm), fifth caudal vertebra (7.5 mm), sixth caudal vertebra (9 mm), seventh caudal vertebra (9.7 mm), eighth caudal vertebra (9.5 mm), ninth caudal vertebra (13 mm), tenth caudal vertebra (14.2 mm), eleventh caudal vertebra (14.3 mm), twelfth caudal vertebra (15.5 mm), thirteenth caudal vertebra (15 mm), fourteenth caudal vertebra (~11 mm), partial fifteenth caudal vertebra (~11 mm), chevrons, incomplete scapulae (~51 mm), coracoids (24.5 mm), partial furcula, incomplete humeri (83 mm), partial radii (~69 mm), partial ulnae (~72 mm), partial metacarpals I, phalanges I-1 (28, 28.4 mm), manual unguals I (17.5 mm), incomplete metacarpals II (~36.6 mm), phalanges II-1 (20.1 mm), phalanges II-2 (27.5 mm), manual unguals II (17.8 mm), incomplete metacarpals III, phalanx III-1 (8 mm), phalanges III-2 (6.5 mm), phalanges III-3 (17.8 mm), manual unguals III (12 mm), manual claw sheaths, ilia (~38 mm), pubes (59.3 mm), partial ischium (~24.5 mm), femora (~67 mm), tibiae (92 mm), fibula (82.4 mm), astragali, calcanea, distal tarsals, metatarsals I (9.9 mm), phalanx I-1 (11 mm), pedal ungual I (~9.8 mm), metatarsus (II 45 mm, III ~47.5 mm, IV 45 mm), phalanges II-1 (12 mm), phalanges II-2 (12.5 mm), pedal unguals II (~14 mm), phalanges III-1 (one proximal; 13.7 mm), phalanx III-2 (11.8 mm), phalanx III-3 (10.5 mm), pedal ungual III (~10 mm), phalanx IV-1 (10 mm), phalanx IV-2 (8.5 mm), phalanx IV-3 (9.5 mm), pedal ungual IV (~12.6 mm), metatarsal V (10.5 mm), pedal claw sheaths, remiges (Wellnhofer, 1988)
(Burgermeister-Muller Museum coll.; chicken wing; ninth specimen) (420 day old juvenile) humerus (70.1 mm), radius (~59 mm), ulna (62 mm), semilunate carpal, metacarpal I (10 mm), phalanx I-1 (22.5 mm), metacarpal II (31.3 mm), phalanx II-1 (~16.5 mm), phalanx II-2 (21 mm), manual ungual II (~15 mm), metacarpal III (27.5 mm), phalanx III-1 (6.3 mm), phalanx III-2 (5 mm), phalanx III-3 (14.4 mm), manual ungual III (~10 mm), remiges (Wellnhofer and Roper, 2005)
(BMNH 37001; London specimen; holotype of Griphosaurus; holotype of Griphosaurus problematicus; holotype of Griphornis longicaudatus; holotype of Archaeopteryx macrura; holotype of Archaeopteryx oweni; proposed neotype of Archaeopteryx lithographica) (.46 m, 370 g, 460 day old subadult) premaxilla, maxillary fragment, partial quadrate, braincase, ninth cervical vertebra, tenth cervical vertebra, first dorsal vertebra (~7 mm), second dorsal vertebra, third dorsal vertebra, fourth dorsal vertebra, fifth dorsal vertebra, sixth dorsal vertebra (~7 mm), seventh dorsal vertebra (~7 mm), eighth dorsal vertebra, ninth dorsal vertebra, tenth dorsal vertebra, eleventh dorsal vertebra (5.5 mm), twelfth dorsal vertebra (5.5 mm), thirteenth dorsal vertebra (5.5 mm), dorsal ribs, gastralia, (sacrum- ~33 mm) first sacral vertebra, second sacral vertebra, third sacral vertebra, fourth sacral vertebra, fifth sacral vertebra, fifth caudal vertebra (5.4 mm), fourth caudal vertebra, fifth caudal vertebra, sixth caudal vertebra (6 mm), seventh caudal vertebra (6.5 mm), eighth caudal vertebra (8 mm), ninth caudal vertebra (~10.5 mm), tenth caudal vertebra (~10.5 mm), eleventh caudal vertebra (11.7 mm), twelfth caudal vertebra (12.3 mm), thirteenth caudal vertebra (13 mm), fourteenth caudal vertebra (12.3 mm), fifteenth caudal vertebra (12.5 mm), sixteenth caudal vertebra (12.4 mm), seventeenth caudal vertebra (11.4 mm), eighteenth caudal vertebra (11.4 mm), nineteenth caudal vertebra (10.5 mm), twentieth caudal vertebra (9.3 mm), twenty-first caudal vertebra (8.5 mm), twenty-second caudal vertebra (7 mm), twenty-third caudal vertebra (4.3 mm), scapulae (46 mm), coracoid, furcula, humeri (75 mm), radii (65 mm), ulnae (67.5 mm), radiale, ulnare, semilunate carpal, distal phalanx I-1, manual ungual I, metacarpal II (34.4 mm), metacarpal III, manual phalanx, ilia (38 mm), pubes (51.5 mm), ischium (~25.5 mm), femora (60.5 mm), tibiae (80.5 mm), astragalus, metatarsal I fragment, phalanx I-1 (8.8 mm), pedal ungual I (~6.8 mm), metatarsal II (~40 mm), phalanx II-1 (11 mm), phalanx II-2 (11 mm), pedal ungual II (~11 mm), metatarsal III (44 mm), phalanx III-1 (12.7 mm), phalanx III-2 (11 mm), phalanx III-3 (~9.5 mm), pedal ungual III (~14 mm), distal phalanx IV-3, phalanx IV-4 , pedal ungual IV (~11 mm), metatarsal V (7.9 mm), remiges, retrices (Meyer, 1861b)
(BSP 1999 I 50; Munich specimen; Solnhofen-Aktien-Verein specimen; seventh specimen; holotype of Archaeopteryx bavarica) (270 day old juvenile) partial skull (~45 mm), mandibles (40 mm), atlas, axis, third cervical vertebra, fourth cervical vertebra, fifth cervical vertebra, sixth cervical vertebra, seventh cervical vertebra, eighth cervical vertebra, ninth cervical neural spine, tenth cervical neural spine, cervical ribs, first dorsal neural spine, partial second dorsal vertebra, third dorsal neural spine, seventh dorsal neural spine, eighth dorsal vertebra, ninnth dorsal vertebra, tenth dorsal vertebra, eleventh dorsal vertebra, twelfth dorsal vertebra, thirteenth dorsal vertebra, dorsal ribs, gastralia, (sacrum 22 mm) first sacral centrum, second sacral centrum, fifth sacral centrum, first caudal vertebra, second caudal vertebra, third caudal vertebra, fourth caudal vertebra, fifth caudal vertebra, sixth caudal vertebra, seventh caudal vertebra, eighth caudal vertebra, ninth caudal vertebra, tenth caudal vertebra, eleventh caudal vertebra, twelfth caudal vertebra, thirteenth caudal vertebra, fourteenth caudal vertebra, fifteenth caudal vertebra, sixteenth caudal vertebra, seventeenth caudal vertebra, eighteenth caudal vertebra, nineteenth caudal vertebra, twentieth caudal vertebra, twenty-first caudal vertebra, chevrons, scapulae (34.5 mm), coracoids (15 mm), partial furcula, humeri (~55 mm), radii (53 mm), ulnae (53 mm), ulnare, semilunate carpal, distal carpal III, metacarpal I (7 mm), phalanges I-1 (20 mm), manual unguals I (9.5 mm), metacarpals II (one distal; 25 mm), phalanges II-1 (12.5 mm), phalanges II-2 (18.5 mm), manual unguals II (10 mm), metacarpals III (one distal; ~23 mm), phalanges III-1 (one partial; 4.9 mm), phalanx III-2 (4.2 mm), phalanges III-3 (12 mm), manual unguals III (6.5 mm), manual claw sheaths, ilium (~27.5 mm), pubis (40 mm), ischia (~16 mm), incomplete femora (~46.5 mm), tibiae (~71.5 mm), fibula (69.5 mm), astragali, calcanea, two distal tarsals, metatarsals I, phalanges I-1 (7.1 mm), pedal ungual I (5.2 mm), metatarsals II (~36 mm), phalanges II-1 (~8 mm), phalanges II-2 (~8 mm), pedal unguals II (7, 7.4 mm), metatarsals III (40.5 mm), phalanges III-1 (10.8 mm), phalanges III-2 (8.5 mm), phalanges III-3 (8.4 mm), pedal unguals III (6.8, 7 mm), metatarsal IV (37 mm), phalanx IV-1 (8 mm), phalanx IV-2 (6 mm), phalanges IV-3 (~5.5 mm), phalanges IV-4 (7 mm), pedal unguals IV (6.2 mm), metatarsal V (~10 mm), pedal claw sheaths, remiges, retrices (Wellnhofer, 1993)
(HMN MB. 1880/81; Berlin specimen; second specimen; holotype of Archaeopteryx seimansii) (.405 m, 260 g; 330 day old juvenile) skull (45 mm), sclerotic ring, mandible (43.5 mm), hyoids, axis (5 mm), third cervical vertebra (6.5 mm), fourth cervical vertebra (9 mm), fifth cervical vertebra (9.5 mm), sixth cervical vertebra (8 mm), seventh cervical vertebra (9 mm), eighth cervical vertebra, ninth cervical vertebra (8 mm), tenth cervical vertebra (7.7 mm), first dorsal vertebra (7.3 mm), second dorsal vertebra (5.5 mm), third dorsal vertebra (5.9 mm), fourth dorsal vertebra (5.7 mm), fifth dorsal vertebra (5.5 mm), sixth dorsal vertebra (5.5 mm), seventh dorsal vertebra (6.1 mm), eighth dorsal vertebra (6.1 mm), ninth dorsal vertebra (6.3 mm), tenth dorsal vertebra (6.2 mm), eleventh dorsal vertebra (6.2 mm), twelfth dorsal vertebra, thirteenth dorsal vertebra, dorsal ribs, gastralia, (sacrum ~31 mm) first sacral vertebra (6.5 mm), second sacral vertebra, third sacral vertebra, fourth sacral vertebra, fifth sacral vertebra, second caudal vertebra (5.3 mm), third caudal vertebra (~4 mm), fourth caudal vertebra (~4 mm), fifth caudal vertebra (6 mm), sixth caudal vertebra (6.5 mm), seventh caudal vertebra (7.3 mm), eighth caudal vertebra (9 mm), ninth caudal vertebra (10.5 mm), tenth caudal vertebra (11.3 mm), eleventh caudal vertebra (11.3 mm), twelfth caudal vertebra (~11.5 mm), thirteenth caudal vertebra (~11.5 mm), fourteenth caudal vertebra (~10.5 mm), fifteenth caudal vertebra (10 mm), sixteenth caudal vertebra (10 mm), seventeenth caudal vertebra (~10 mm), eighteenth caudal vertebra (~9.5 mm), nineteenth caudal vertebra (8.5 mm), twentieth caudal vertebra (8 mm), twenty-first caudal vertebra (7.2 mm), twenty-second caudal vertebra (5.5 mm), twenty-third caudal vertebra, scapulae (42 mm), coracoids, humeri (63.5 mm), radii (54.4 mm), ulnae (55 mm), radiales, ulnares, semilunate carpals, distal carpal III, metacarpals I (8.3 mm), phalanges I-1 (20.5 mm), manual unguals I (~12.5 mm), metacarpals II (28 mm), phalanges II-1 (15.5 mm), phalanges II-2 (19.4 mm), manual unguals II (~16 mm), metacarpals III (24.8 mm), phalanges III-1 (6.4 mm), phalanges III-2 (4.2 mm), phalanges III-3 (12.3 mm), manual unguals III (~9.5 mm), manual claw sheaths, ilium (~32 mm), pubis (48 mm), incomplete ischium (~20 mm), femora (52.2 mm), tibiae (71 mm), astragalus, calcaneum, distal tarsal III, distal tarsal IV, metatarsal I, phalanges I-1 (5.2, 5.5 mm), pedal ungual I (5.5 mm), metatarsal II (~35 mm), phalanx II-1 (8.2 mm), phalanx II-2 (7 mm), pedal ungual II (12.5 mm), metatarsals III (~37 mm), phalanges III-1 (9.6 mm), phalanges III-2 (9 mm), phalanges III-3 (8.2 mm), pedal unguals III (8.8 mm), metatarsal IV (~32.5 mm), phalanges IV-1 (7 mm), phalanges IV-2 (6.4, 6.6 mm), phalanges IV-3 (4.9 mm), phalanges IV-4 (5.6, 5.8 mm), pedal unguals IV (6.8 mm), body feathers, remiges, retrices (Dames, 1884)
(JM SoS 2257; Eichstatt specimen; fifth specimen; holotype of Archaeopteryx recurva) (.29 m, 69 g; 110 day old juvenile) skull (39 mm), sclerotic ring, mandible (36.5 mm), atlas, axis (3.7 mm), third cervical vertebra (~4.5 mm), fourth cervical vertebra (~6 mm), fifth cervical vertebra (~7 mm), sixth cervical vertebra (~5.5 mm), seventh cervical vertebra (~5 mm), eighth cervical vertebra (~5 mm), ninth cervical vertebra (~4.5 mm), tenth cervical vertebra (~3.5 mm), cervical ribs, first dorsal vertebra (4 mm), second dorsal vertebra, partial third dorsal vertebra, partial fifth dorsal vertebra (4 mm), sixth dorsal vertebra (4 mm), seventh dorsal vertebra (~4 mm), eighth dorsal vertebra (4.5 mm), ninth dorsal vertebra (~5 mm), tenth dorsal vertebra (~4.5 mm), eleventh dorsal vertebra, twelfth dorsal vertebra (4 mm), thirteenth dorsal vertebra (4 mm), dorsal ribs, gastralia, (sacrum ~16.5 mm), first sacral centrum (3.7 mm), second sacral centrum (3.4 mm), third sacral centrum (3.1 mm), fourth sacral centrum (3.2 mm), fifth sacral centrum, first caudal vertebra (3 mm), second caudal vertebra (3.3 mm), third caudal vertebra (3.5 mm), fourth caudal vertebra (~4 mm), fifth caudal vertebra (4.7 mm), sixth caudal vertebra (5.4 mm), seventh caudal vertebra (6.4 mm), eighth caudal vertebra (7.2 mm), ninth caudal vertebra (7.9 mm), tenth caudal vertebra (8.4 mm), eleventh caudal vertebra (8.5 mm), twelfth caudal vertebra (8.6 mm), thirteenth caudal vertebra (8.3 mm), fourteenth caudal vertebra (8.3 mm), fifteenth caudal vertebra (8 mm), sixteenth caudal vertebra (7.7 mm), seventeenth caudal vertebra (7.4 mm), eighteenth caudal vertebra (6.9 mm), nineteenth caudal vertebra (6.6 mm), twentieth caudal vertebra (~5.5 mm), twenty-first caudal vertebra (4.2 mm), twenty-second caudal vertebra (4 mm), twenty-third caudal vertebra, seventeen chevrons, incomplete scapulae, partial coracoids, humeri (41.5 mm), radii (35 mm), ulnae (36.5 mm), radiales, ulnare, semilunate carpals, distal carpals III, metacarpals I (one proximal; 5.5 mm), phalanges I-1 (one distal; 15.6 mm), manual unguals I (9.8 mm), metacarpals II (one incomplete; 17.8 mm), phalanges II-1 (10.2 mm), phalanges II-2 (15.1 mm), manual unguals II (10.8 mm), metacarpals III (one incomplete; 16.5 mm), phalanx III-1 (4.2 mm), phalanx III-2 (3 mm), phalanx III-3 (9.8 mm), manual unguals III (6.5 mm), manual claw sheaths, incomplete ilium (~20 mm), pubes (31.5 mm), ischia (14.5 mm), femora (37 mm), tibiae (~53 mm), fibula (50.5 mm), astragali, distal tarsal III, distal tarsal IV, metatarsals I, phalanges I-1 (5.5 mm), pedal unguals I (3.5 mm), partial metatarsals II (28.3 mm), phalanges II-1 (~7.1 mm), phalanges II-2 (7 mm), pedal unguals II (5.8 mm), metatarsals III (30.2 mm), phalanges III-1 (one proximal; 9 mm), phalanges III-2 (8 mm), phalanges III-3 (7 mm), pedal unguals III (5.4, 4.8 mm), metatarsals IV (27.3 mm), phalanges IV-1 (6.1 mm), phalanges IV-2 (5 mm), phalanges IV-3 (4.6, 4.7 mm), phalanges IV-4 (4.9 mm), pedal unguals IV, metatarsals V (one partial; 6.5 mm), pedal claw sheaths, remiges, retrices (Wellnhofer, 1974)
(Opitsch coll.; Maxberg specimen; third specimen; lost) fifth cervical centrum, sixth cervical centrum, seventh cervical centrum, eighth cervical centrum, ninth cervical centrum, tenth cervical centrum, first dorsal centrum, second dorsal centrum, third dorsal centrum, fourth dorsal centrum, fifth dorsal centrum, sixth dorsal centrum, seventh dorsal centrum, eighth dorsal centrum, ninth dorsal centrum, tenth dorsal centrum, eleventh dorsal centrum, twelfth dorsal centrum, thirteenth dorsal vertebra, dorsal rib fragments, gastralia, first sacral vertebra, second sacral vertebra, third sacral vertebra, fourth sacral vertebra, fifth sacral vertebra, first caudal centrum, second caudal centrum, third caudal centrum, incomplete scapula, coracoid, incomplete furcula, humeri (one incomplete; 72 mm), radii (63 mm), ulnae (one incomplete; ~62 mm), metacarpals I (~10 mm), distal phalanx I-1, manual unguals I (~12 mm), metacarpals II (~33 mm), phalanges II-1 (19 mm), phalanges II-2 (~22 mm), manual unguals II (~15 mm), metacarpals III (one proximal; 30 mm), phalanges III-1, phalanges III-2, phalanx III-3 (~16 mm), manual unguals III, partial ilium, femur (~58 mm), tibiae (one partial; ~79.5 mm), incomplete fibula, distal tarsal, metatarsal I, metatarsus (one proximal; II ~38 mm, III ~42 mm, IV ~39 mm), phalanx II-1 (~9.5 mm), phalanx II-2 (~10 mm), phalanx III-1 (~11 mm), phalanx III-2 (~10.5 mm), phalanx IV-1, phalanx IV-2, remiges, hindlimb feathers (Heller, 1959)
(TM 6928/29; Haarlem specimen; Teyler specimen; fourth specimen; holotype of Pterodactylus crassipes) (350 day old juvenile) two dorsal centra, dorsal rib fragments, gastralia, incomplete radii, incomplete ulnae, metacarpal I (10 mm), phalanx I-1 (23.3 mm), manual ungual I (9.7 mm), incomplete metacarpal II, distal phalanx II-2, manual ungual II, incomplete metacarpal III (29.4 mm), manual ungual III (10.5 mm), distal pubis, incomplete femora (~54 mm), incomplete tibiae (~80 mm), incomplete fibula, phalanx I-1, pedal ungual I, incomplete metatarsal II, phalanges II-1, phalanges II-2, pedal unguals II, incomplete metatarsal III (~48 mm), phalanges III-1, phalanx III-2, phalanx III-3, pedal unguals III, incomplete metatarsal IV, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, two pedal phalanges, remiges (Ostrom, 1972)
(WDC-CSG-100; Thermopolis specimen; tenth specimen) (1 year old juvenile) skull (52.9 mm), sclerotic ring, mandibular fragment, five dentary teeth, partial hyoid, six cervical vertebrae, partial seventh dorsal vertebra, partial eighth dorsal vertebra, partial ninth dorsal vertebra, partial tenth dorsal vertebra, partial eleventh dorsal vertebra, partial twelfth dorsal vertebra, partial thirteenth dorsal vertebra, dorsal ribs, gastralia, first sacral centrum, second sacral centrum, third sacral centrum, fourth sacral centrum, fifth sacral fragment, first caudal vertebra, second caudal vertebra (3.8 mm), third caudal vertebra (4.2 mm), fourth caudal vertebra (4.2 mm), fifth caudal vertebra (5.4 mm), sixth caudal vertebra (6.5 mm), seventh caudal vertebra (7.9 mm), eighth caudal vertebra (9.5 mm), ninth caudal vertebra, tenth caudal vertebra (~10 mm), eleventh caudal vertebra (11.1 mm), twelfth caudal vertebra (10.9 mm), thirteenth caudal vertebra (10.9 mm), fourteenth caudal vertebra (10.6 mm), fifteenth caudal vertebra (10.6 mm), sixteenth caudal vertebra (10.1 mm), seventeenth caudal vertebra (9.1 mm), eighteenth caudal vertebra (9.1 mm), nineteenth caudal vertebra, partial twentieth caudal vertebra, chevrons, scapulae (35 mm), coracoids, furcula, humeri (one proximal; 56.9), radii, ulnae (50.9 mm), semilunate carpal, metacarpals I (6.6 mm), phalanges I-1 (19.5 mm), manual unguals I, metacarpals II (23.5 mm), phalanges II-1 (12.8 mm), phalanges II-2 (18.6 mm), manual unguals II, metacarpals III (22 mm), phalanges III-1 (4.8 mm), phalanges III-2 (4.2 mm), phalanges III-3 (12.9 mm), manual ungual III, manual claw sheaths, partial ilium, pubes, ischium, femora (one incomplete; 50.3 mm), tibiae (one incomplete; 74.6 mm), fibula, astragali, calcaneum, metatarsals I, phalanges I-1 (6.1 mm), pedal unguals I, metatarsals II (35.1 mm), phalanges II-1 (10.6 mm), phalanges II-2 (one proximal; 8.8 mm), pedal ungual II, metatarsals III (39.6 mm), phalanges III-1 (one proximal; 10.8 mm), phalanx III-2 (9.6 mm), phalanx III-3 (7.8 mm), pedal ungual III, metatarsals IV (36.3 mm), phalanges IV-1 (7.5 mm), phalanges IV-2 (one proximal; 6.6 mm), phalanx IV-3 (5.6 mm), phalanx IV-4 (5.6 mm), pedal ungual IV, pedal claw sheaths, remiges, retrices (Mayr et al., 2005)
Early Tithonian, Late Jurassic
Mörnsheim Formation, Germany
?(private coll.; eighth specimen) (320 day old juvenile) skull, scapulae, humeri (one incomplete), radius, ulna, semilunate carpal, metacarpal I, phalanx I-1, metacarpal II, metacarpal III, fragments (Mauser, 1997)
Comments-
Haarlem specimen- Meyer (1857) named TM 6928/29 Pterodactylus (Rhamphorhynchus) crassipes, decribing it in detail in 1860. The only other author to consider the specimen was Wellnhofer (1970), who believed it was closest to Scaphognathus, making it S. crassipes. Ostrom (1970) identified it as an Archaeopteryx specimen many years later. He later described it in more detail in 1972(b), noting that since crassipes has priority over lithographica chronologically, the species should technically be called Archaeopteryx crassipes. However, he petitioned the ICZN that same year (a) to conserve the name Archaeopteryx lithographica, which was upheld by the ICZN in 1977 as opinion #1070 (Melville, 1977).
London specimen and feather- Meyer (1861a) first mentioned and described the holotype feather discovered in 1860, but did not name it. He later (1861b) referred to the feather and mentioned the then undescribed London specimen discovered that year, stating that "For the denomination of the animal I consider the term Archaeopteryx lithographica as appropriate", but exactly which specimen (if not both) he considered "the animal" is ambiguous. The title suggests the feather is the holotype, but this was written by an anonymous editor. In his later (1862a) paper, he indicates the name Archaeopteryx lithographica was meant to be tied to the feather, making it the holotype ("The fossil feather presented by me may come from a similar animal, for which I have chosen the denomination Archaeopteryx lithographica"). This was misunderstood by many subsequent authors, including de Beer (1954), who have viewed the London specimen as the holotype instead. Wagner (1962a) described the London specimen as a new genus of pterosaur- Griphosaurus, being unaware of Meyer's 1861b paper. While the paper was dated 1861, it wasn't published until January 20th, 1862. Woodward (1962) used the name Archaeopteryx lithographica, but stated Owen would describe the London species under the name Griphornis longicaudatus. A footnote indicates Owen had decided to retain the name Archaeopteryx though, as indeed did happen in his 1863 paper. More confusingly, Woodward uses the name "Griphosaurus problematicus Wagner, 1861" in the plate label for the London specimen, though Wagner never used a species name in his 1862 ("1861") publication. Owen (1863a) made the London specimen the holotype of his new species Archaeopteryx macrura (misspelled macrurus in his 1863a publication, but corrected in 1863b), since he considered its feathers different from the A. lithographica holotype. Several later authors followed Owen's usage (Dames, 1884; Lambrecht, 1933). The new combination Griphosaurus longicaudatus has been listed as deriving from Owen (1862), but Buhler and Bock (2002) indicate this was a mistaken attribution by Brodkorb (1963). Petronievics (1921) used the name Archaeopteryx oweni for the London specimen without justification, so it is clearly a junior synonym. In 1960, Swinton petitioned the ICZN to place Archaeopteryx lithographica on the Official List of Generic/Specific Names in Zoology, and to add Griphosaurus, Griphornis longicaudatus, Griphosaurus problematicus, Archaeopteryx macrurus and Archaeopteryx oweni to the Official Index of Rejected and Invalid Generic/Specific Names in Zoology, which was upheld by Riley and China in 1961 as opinion #607. Bock and Buhler (2007) have recently petitioned the ICZN to make the London specimen the neotype of Archaeopteryx lithographica, since authors have interpreted Meyer's intent in different ways, and nearly all references have based the taxon on the more diagnostic skeleton as opposed to the feather. The issue has yet to be decided as of April 2009. The feather was recently redescribed by Griffiths (1996), who noted it differed from the London and Berlin specimens in being smaller, broader and more asymmetrical. He proposed that both taphonomic and taxonomic explanations were possible, and his analysis indicates the feather cannot be definitively referred to Archaeopteryx lithographica in any case. Benton and Gower (2002) reveal Walker had written a letter in 1985 also wondering about the possibility the feather was taxonomically distinct from the skeletons, though it was never published. The London specimen was most recently described in detail by de Beer (1954).
Berlin specimen- The Berlin specimen was discovered in 1877 and variously regarded as conspecific with the London specimen (Dames, 1884), or different due to size (Seeley, 1881). Later, Dames (1897) made the holotype of a new species- Archaeopteryx seimensii due to dental and pelvic characters. Subsequently, Petronievics (as a footnote in Petronievics and Woodward, 1917) separated it further as a new genus- Archaeornis. This was due to his view the expanded calcitic mass of the London specimen was not homologous to the pubic boot of the Berlin specimen, that the latter lacked a pubic symphysis, and other unstated pectoral and pelvic differences. Additional differences later provided by Petronievics (1921, 1925) include teeth with a circular cross section, proximal carpals ossified, metacarpal III with cylindrical section, unfused scapulocoracoid, narrow coracoid, unfused tibiotarsus, pubis and ischium at a greater angle, obturator foramen absent in pubis, straight ischium, and ischium poorly ossified distally. Petronievics later (1927, 1950) went so far as to place Archaeopteryx as a pan-paleognath and Archaeornis as a pan-neognath. Nopcsa (1923) noted most of these characters were preservational (carpal number; pubic foot size; ischial shape) or ontogenetic (length of pubic symphysis; ischial ossification; tibiotarsal fusion), while others were misinterpretations (tooth cross section; scapulocoracoid fusion; pubic angle; obturator foramen). He and de Beer (1954) synonymized it with A. lithographica, which has been the consensus until recently. In 2002, Elzanowski reinstated Archaeopteryx seimensii based on the smaller size, lack of a cuppedicus fossa on the ilium, lack of a ventral hook on the ilial preacetabular process, and pedal unguals without flexor tubercles. Senter and Robins (2003) disagreed, finding flexor tubercles in all Archaeopteryx specimens, and believing the ilial features to become more developed with age. Mayr et al. (2007) confirmed the flexor tubercles are more poorly developed and noted the metatarsus was more slender, but did not comment on ilial morphology.
Maxburg Specimen- The Maxberg specimen was discovered in 1956 and described in 1959 by Heller. It was privately owned by Opitsch, though on display at the Maxberg Museum from 1959-1982. Unfortunately, when Opitsch died in 1991, the specimen could not be found and was seemingly stolen (Abbott, 1992). Mayr et al. (2007) assigned it to A. lithographica (as opposed to A. seimensii) due to its robust metatarsus.
Eichstatt specimen- The Eichstatt specimen was discovered in 1951 and originally identified as a juvenile Compsognathus. This was initially described by Mayr (1973) as perhaps a new species of Archaeopteryx, and later in detail by Wellnhofer (1974) as a juvenile A. lithographica. Howgate (1984) separated it from the other specimens then known as a new species, Archaeopteryx recurva. This was based on the small size, recurved teeth, supposedly absent furcula, more vertical pubis, short pubic symphysis, elongate tibia (1.42 times femoral length compared to 1.30-1.38), elongate metatarsus (1.67 times femoral length compared to 1.43-1.47) and unfused metatarsus. He later used these characters to separate it further as a new genus- Jurapteryx. However, almost all later authors have believed it to be a juvenile specimen of Archaeopteryx lithographica (Paul, 1988; Wellnhofer, 1992), with the furcula missing due to taphonomy and the pubes of the London and Berlin specimens rotated too far posteriorly. Houck et al. (1990) determined the limb proportions of Archaeopteryx specimens were consistant with allometric variation that would be expected due to ontogeny, which has been confirmed for subsequent specimens by Senter and Robins (2003) and Bennett (2008). Christiansen's (2006) allometric study concluded the data supported multiple species at least as well as it did a single species, but his rationale was flawed (Bennett, 2008). Elzanowski (2002) could not confirm separation of the Eichstatt specimen as a distinct species, while Senter and Robins (2003) noted theropods such as Coelophysis decrease curvature of teeth with ontogeny, suggesting the same explanation for the Eichstatt specimen's teeth.
Solnhofen specimen- The Solnhofen specimen was discovered in a private collection in 1987 and initially identified as a Compsognathus until it was examined in 1988 by Wellnhofer and described by him that year as a new specimen of Archaeopteryx lithographica. Longer descriptions appeared later in 1988 and in 1992. In 2001, Elzanowski separated the specimen as a new taxon - Wellnhoferia grandis. This was based on the large size, short tail as reconstructed (~16-17 vertebrae), unfused scapulocoracoid, shorter manual ungual I compared to phalanx I-1 (33%), manual phalanges I-1 and II-2 deeper, manual phalanges III-1 and III-2 sutured, more retroverted pubis (~128 degrees), metatarsals II and IV subequal in length, pedal phalanx II-2 longer than II-1, short pedal digit IV with only four phalanges, pedal ungual IV longest phalanx in digit, and pedal ungual IV straight with flexor tubercle widely separated from its base. In 2002, he added a proximally tapering metatarsal II to the diagnosis. Senter and Robins (2003) agree it is distinct, and Mayr et al. (2007) agree it is distinct from the Berlin and Munich specimens, but disputed differences between it and the London specimen (synonymizing it with A. lithographica). In particular, they note the proportions of manual digit I phalanges and number of phalanges in pedal digit IV are not preserved in the London specimen, and the tail length is uncertain in the Solnhofen specimen (it was estimated to be short by Elzanowski due to the rapid decrease in central length distally). The specimens are also both larger than other specimens and share additional characters (premaxillary teeth with constricted crowns; similar limb proportions; stout metatarsus; well developed flexor tubercles on pedal unguals). However, the London specimen has a fused scapulocoracoid, pedal phalanx II-2 equal in length to II-1, a more elongate pedal digit IV, and a curved pedal ungual IV.
Munich specimen- The next specimen was discovered in 1992 and first called the Solnhofen-Aktien-Verein specimen, then later the Munich specimen. It was described in 1993 as a new species of Archaeopteryx, A. bavarica. This was based on the small size, twelve dentary teeth, dentary interdental plates, ossified sternum, elongate tibia (1.48 times femoral length), hindlimb elongate compared to humerus (3.56 times). Elzanowski (2002) added further distinguishing characters- anterior dentary tooth crowns compressed; third and fourth cervical neural spines tall, equaling about a third of vertebral height; ulna elongate compared to humerus (96%); ilium lacking ventral hook on preacetabular process; no cuppedicus fossa on ilium; pedal unguals lack flexor tubercles. Senter and Robins (2003) determined the tibial, hindlimb and ulnar lengths were all explainable by allometry, believed the ilial features could be absent due to ontogeny, noted tooth compression could be too (as in tyrannosaurids), and stated pedal ungual flexor tubercles are actually present. Wellnhofer and Tischlinger (2004) determined the supposed sternum of the Munich specimen is really a coracoid. Mayr et al. (2007) noted their new specimen is intermediate between the Munich and Berlin specimens in size, hindlimb and ulnar proportions, while its tibia is longer than the Munich specimen. Considering the misidentified sternum, and that the ilial and pedal ungual characters are supposedly shared with the Berlin specimen, they synonymized A. bavarica with A. seimensii.
New specimens- The eighth specimen is in a private collection and was discovered in 1997. It has yet to be described, but was noted by Mauser (1997) in a brief article. As it derives from a younger formation, it may be distinct.
The ninth specimen was initially announced by Roper (2004) after it was collected that year. It is the oldest specimen and has immature bone grain. Wellnhofer and Roper (2005) described it in detail, assigning it to A. lithographica instead of A. bavarica (based on ulnar proportions).
The Thermopolis specimen was originally recognized in 2001 and first briefly described in 2005 (Mayr, 2005; Mayr et al., 2005) before being described in detail by Mayr et al. (2007). Though initially only assigned to Archaeopteryx sp. (Mayr et al., 2005), they later assigned it to A. seimensii, in which they also include the Munich specimen. This was based on small size, slender metatarsus, poorly developed pedal ungual flexor tubercles, as well as characters differing from the Solnhofen specimen (long manual ungual I; metatarsals II and IV not subequal; pedal digit IV with five phalanges; pedal ungual IV shorter than phalanx IV-1). They further note that the ischium exhibits a different morphology than the London specimen, which added evidence to separate seimensii from lithographica.
Resolving the species problem- As can be seen from the above discussions, recent papers have placed the known specimens in one (Paul, 2002), two (Senter and Robins, 2004; Mayr et al., 2007) or four (Elzanowski, 2002) species, often based on similar characters. These will be examined below to determine how many species are based on good evidence.
Size is not evidence of multiple species, as no specimen is obviously adult, and young theropods (includsing basal birds) were precocial in regard to their ossification timing (e.g. Scipionyx, juvenile Yixian enantiornithines). The latter disproves Howgate's (1984) suggestion that well ossified elements indicate the Eichstatt specimen is an adult. More recently, Erickson et al. (2009) have analyzed the histology of the Munich specimen and noted this and other specimens (including the Solnhofen specimen) show fibrous surface texture with long striae on long bones typical of young individuals.
Tooth recurvature is polymorphic in every specimen (Howgate, 1984). In the London specimen, the third premaxillary tooth and maxillary teeth 1, 3 and 6 are straight, but an isolated premaxillary tooth is recurved. In the Berlin specimen, the first premaxillary tooth, and maxillary teeth 1 and 6 are straight, but premaxillary teeth 2-4 and maxillary teeth 1 and 3-5 are recurved. In the Eichstatt specimen, maxillary teeth 3 and 9, and dentary teeth 2, 4-6 and 10-11 are straight, but all premaxillary teeth, maxillary teeth 1-2 and 4-6, and dentary tooth 7 are recurved. In the Thermopolis specimen, premaxillary teeth 1-2 are straight, but premaxillary teeth 3-4 and maxillary teeth 4-8 are recurved. In the Solnhofen specimen, premaxillary teeth 1-2 and 4, maxillary teeth 4-7 and perhaps four dentary teeth (4-7?) are straight, but premaxillary tooth 3 and maxillary teeth 2 and 3 are recurved. The narrow tips of the Eichstatt specimen's teeth are directly due to the more acute angle of a recurved crown, and some of its teeth (e.g. second premaxillary tooth) have apical wear facets as in the London specimen. The London's and Munich's specimens teeth appear flatter because they are exposed in lingual view, unlike the Berlin specimen. The presence of one less dentary tooth in the Munich specimen compared to the Eichstatt specimen is within the normal range of interspecific variation in theropods (e.g. Currie, 2003). The presence of interdental plates in the Munich specimen is probably a misinterpretation (Martin and Stewart, 1999), so it it similar to the London specimen in this regard. So the only difference is in the frequency of tooth recurvature, which is actually less in the Eichstatt specimen than the Berlin and Thermopolis specimens, while the sample size of the London specimen (four teeth) is too low for useful comparison. A large sample of Saurornitholestes teeth shows generally decreasing curvature with increasing size, which shows curvature could be ontogenetic as described by Howgate (1984) for Varanus and Senter and Robins (2004) for Coelophysis. There are a number of cranial differences between the Berlin and Eichstatt specimens which may be due to ontogeny (the Berlin specimen has a more convex ventral maxillary edge, differently sized and placed maxillary fenestrae, deeper dentary; similar to ontogenetic changes in tyrannosaurids), though if the subnarial nasal process being absent isn't preservational, it may be of taxonomic importance. The convexity doesn't seem to be shared by the Solnhofen or Thermopolis specimens. The Thermopolis specimen has a nasal subnarial process and maxillary fenestrae that resemble the Eichstatt specimen's more, but the latter are still differently shaped.
The neural spines of cervical vertebrae three and four are comparable in height in the Eichstatt (3rd 28% of vertebral height; 4th 28%), Berlin (3rd 29%; 4th 28%) and Munich (3rd 29%; 4th 30%) specimens. While it's true the tail of the Solnhofen specimen is broken through the fifteenth caudal, and thus the total number of vertebrae is uncertain, Elzanowski (2001) based his lower estimate on the sharp decrease in centrum length between the thirteenth and fourteenth caudal (the latter is 73% of the former). This compares to 95% in the London specimen, 92% in the Munich specimen, ~91% in the Berlin specimen, 100% in the Eichstatt specimen, and 97% in the Thermopolis specimen. Contrary to Elzanowski though, the fifteenth caudal is not necessarily as short, since only the proximal half is preserved. Other Archaeopteryx specimens can have isolated shorter vertebrae before the tail tip, for instance caudal 17 of the Munich specimen is 74% as long as caudal 16, even though caudals 18 and 19 are 88% and 105% as long as caudal 16. While Elzanowski argues the sudden thinness of these last two vertebrae shows they were near the tail tip, Wellnhofer (1992) notes the tail is twisted at caudals 12-13 to show the following vertebrae in dorsal aspect. As in the Thermopolis specimen, distal caudal vertebrae are taller than they are wide, explaining the thinness. Thus the tail of the Solnhofen specimen was not necessarily shorter than the others'. One vertebral difference in specimens that does seem real is the height of the dorsal neural spines, which using the twelfth dorsal vertebra for comparison are 28% of vertebral height in the Eichstatt specimen, 26% in the Solnhofen specimen, 38% in the Munich specimen, ~29% in the Berlin specimen and ~29% in the Maxburg specimen. Also, the Thermopolis specimen has its last dorsal sutured to the sacrum, giving it six sacral vertebrae. This is certainly not the case for the Eichstatt, Maxburg and London specimens, and doesn't seem to be for the Munich specimen either. The Eichstatt specimen seems to lack caudal neural spines, wheras they are present in the Munich and Solnhofen specimens.
The scapula and coracoid are apparently fused in the London specimen, tightly connected in the Berlin and Maxburg specimens, and more loosely connected in the Eichstatt and Solnhofen specimens. They are also unfused in the Munich and Thermopolis specimens. However, scapulocoracoid fusion is variable within other taxa as well, including Struthiomimus, Dromiceiomimus and Caudipteryx. Maniraptoran coracoids are complex bones, which makes comparing their shapes difficult. For instance, the right coracoid of the Thermopolis specimen and left coracoid of the London specimen (as illustrated by Ostrom, 1976) appear to be short, but that's probably because their proximal portion is bent into the sediment. The proximal portion is illustrated in the London specimen by Petronievics and Woodward (1917), and also makes the coracoid elongate in the Munich specimen, while the bend can be observed in the lateral views of the Solnhofen and Thermopolis left coracoids. The medial margin of the London specimen's coracoid has two notches which are not seen in the Munich or Thermopolis specimens. The absence of a furcula in the Eichstatt specimen is near certainly taphonomic, while the supposed sternum in the Munich specimen is a coracoid.
Ulnohumeral ratios vary between ~86% (Maxberg), 87% (Berlin), ~87% (Solnhofen), 88% (Eichstatt and ninth), 89% (Thermopolis), 90% (London), and ~96% (Munich). While this a large amount of variation, is is continuous and also known in Sapeornis. All specimens probably had four carpals (radiale, ulnare, semilunate carpal, distal carpal III), though these are easily lost. In particular, the London specimen is seemingly missing proximal carpals, the Eichstatt specimen lacks the ulnare on the right hand (the bone labeled as an ulnare is probably distal carpal III), the left manus of the Munich specimen lacks the radiale, only the semilunates are visible in the Thermopolis specimen and ninth specimen, and the Maxburg specimen seems to lack preserved carpals. Contrary to Elzanowski (2001), manual ungual I is not short compared to phalanx I-1 in the Solnhofen specimen. However, manual phalanx I-1 of the Solnhofen specimen is 1.39 times as long as phalanx II-1, compared to 1.36 times in the ninth specimen, 1.60 times in the Munich specimen, 1.32 times in the Berlin specimen, 1.53 times in the Eichstatt specimen, and 1.52 times in the Thermopolis specimen. Similar variation is known in other coelurosaurs however (Sapeornis, Dromiceiomimus, Gorgosaurus). Elzanowski (2001) noted manual phalanx I-1 is more robust in the Solnhofen and Haarlem specimens (minimum height 8.4% and 8.2% of phalanx length respectively compared to the Berlin (6%), Eichstatt (5.84%) and Munich (5.75%) specimens, and this is also true compared to the ninth (6.56%) and Thermopolis (7.4%) specimens. Yet the latter two also close the gap in ratios, making them seem less important for dividing specimens. Similarly, the Thermopolis specimen (~8.1%) fills the gap between the Solnhofen (8.9%) and Berlin (6.2%), Eichstatt (6.9%) and Berlin (6.2%) specimens when it comes to robusticity of manual phalanx II-2. The cross section of metacarpal III was said to distinguish the London and Berlin specimens, but this has not been studied in further specimens. Metacarpal III is more bowed with an intermetacarpal gap in the Solnhofen, Munich, Thermopolis and ninth specimens compared to the Berlin and Eichstatt specimens, but this may be due to its orientation. Manual phalanges III-1 and III-2 are sutured in the Solnhofen specimen (as in Jinfengopteryx and the Didactylornis type), but not in the Berlin, Maxburg, Eichstatt, Munich, ninth and Thermopolis specimens. The ratio between phalanges III-2 and III-1 varies between 66% (Berlin), ~69% (Maxberg), 71% (Eichstatt), 79% (ninth), 81% (Solnhofen), 86% (Munich) and 88% (Thermopolis). While this is quite a range, it is also gradational and seen in some other taxa (Struthiomimus, Dromiceiomimus).
The Eichstatt, Solnhofen and Berlin specimens have an unexpanded preacetabular processes, the London and probably the Munich and Thermopolis specimens have ventrally expanded processes. Senter and Robins (2003) suggested this could be due to ontogeny, but juvenile tyrannosaurids, Juravenator, Gallimimus, therizinosauroids, Microvenator, Bambiraptor and Scansoriopteryx all have expanded preacetabular processes, though the subadult Yangchuanosaurus shangyouensis holotype lacks one while the larger Y. magnus holotype has one. The preacetabular process varies in length between specimens, from 54% of pubic peduncle plus acetabulum length in the Solnhofen specimen to 89% (Eichstatt), ~111% (Munich), 120% (London) and 160% (Berlin). Elzanowski (2002) claimed the Berlin and Munich specimens lack an m. cuppedicus fossa on their ilia, unlike the London specimen, but such a fossa is clearly visible in the Berlin specimen (Ostrom, 1976- figure 20) while the Munich specimen seems to not preserve a lateral surface (Wellnhofer, 1993- plate 9). The Eichstatt specimen's ilium is only visible in medial view, while the Solnhofen specimen is too poorly preserved to tell. The London specimen differs from the Berlin, Eichstatt, Munich and Solnhofen specimens in having a dorsally concave ilium. The pubic angle of Archaeopteryx has been quite controversial, but is articulated at 3 degrees posterior to vertical in the Munich specimen. The pubis is disarticulated in the London, Berlin, Eichstatt, Solnhofen and Thermopolis specimens, so its angle cannot be used to distinguish species. The London and Thermopolis specimens have posterior pubic boots partially replaced by calcite (originally from cartilage?), while the Eichstatt, Munich and Berlin specimens seem to have more ossified pubic boots, but this could be ontogenetic. The London specimen differs from the Haarlem, Berlin and Eichstatt specimens (Ostrom, 1976) in having a transversely expanded pubic boot. The length of the pubic apron varies between 36% (Berlin), 39% (Solnhofen), 40% (Eichstatt), ~46% (London) and ~47% (Thermopolis), but may be overestimated in the last two due to their incompletely ossified distal ends. The obturator foramen identified by Petronievics in the London specimen is a pneumatic fossa (Christiansen and Bonde, 2000), and whether it is present in other specimens is uncertain due to a lack of posterior pubic exposure. The ischia of specimens differ a great deal, but this has not been recently and explicitly described. The London specimen has an obturator foramen (unique among maniraptoriforms), while a fossa is present in the Eichstatt and Munich specimen, and the Thermopolis specimen seemingly lacks either. The proximoventral edge of the ischium is convex in the London specimen, unlike the Berlin, Eichstatt, Munich and Thermopolis specimens. The obturator process projects ventrally in the Munich and Thermopolis specimens, a bit less in the Eichstatt specimen, and not at all in the London specimen. The distodorsal process (at midlength) varies from a rounded bump in the London specimen and low angularity in the Munich specimen to a large triangular spine in the Solnhofen and especially Eichstatt specimens, to a large flange with a posterior notch in the Thermopolis specimen. Similarly, the proximodorsal process varies from a low peak (Berlin, Eichstatt, Thermopolis), to a slender point (Solnhofen), to a massive block-like process (Munich, London). The London specimen's further differs in having a notch proximally, making it rectangular. Ischial variation has not been examined much in other taxa, though Microraptor varies in the angle of the distal obturator process edge, obturator process expansion, shaft depth and ventral convexity proximal to the obturator process. Mirischia famously varies in the presence of an obturator process and notch. Tyrannosaurus varies in obturator process size and orientation, as well as proximodorsal process size, shaft curvature and distal expansion. The differences observed in Archaeopteryx specimens may be due to intraspecific variation as well.
Hindlimb ratios are explainable by allometry (Bennett, 2008), as are the more robust metatarsi of large specimens (Maxberg, Solnhofen) compared to smaller ones (Eichstatt, Munich, Thermopolis) (compare to juvenile tyrannosaurids vs. adults). Tibiotarsal and tarsometatarsal fusion is controversial in Archaeopteryx. It seems absent in the Eichstatt and Munich specimens. Tibiotarsal and metatarsal fusion are absent in the Thermopolis specimen, though the astragalus and calcaneum could be fused. In the Berlin and London specimens, there is no evidence for metatarsal fusion and at least the ascending process of the astragalus remains unfused to the tibia. Though Ostrom (1976) claimed the distal tarsal in the Maxberg specimen was "at least partially fused" to the metatarsus, he said the same of the Eichstatt specimen which seems to be untrue. Metatarsals II-IV of the Maxberg specimen are indistinguishable proximally and fused as determined by x-rays. The Solnhofen specimen lacks tibiotarsal and tarsometatarsal fusion, but metatarsals II-IV seem to be partially fused proximally. Fusion could be ontogenetic, of course, as the Solnhofen and Maxberg are among the largest specimens. The metatarsal II/IV ratio varies between 97% (Thermopolis), ~97% (Munich, Maxberg), 100% (Solnhofen), 104% (Eichstatt), and ~108% (Berlin). Tyrannosaurus has a similar variation (91-103%), and that of Dromiceiomimus is slightly less (90-97%). While Elzanowski (2001) emphasized the equal lengths in the Solnhofen specimen, it is intermediate between the other specimens and thus not an outlier. The proximally tapering second metatarsal in the right foot of the Solnhofen specimen is probably due to distortion as it is not present in the left foot. The phalanx II-2/II-1 ratio varies between 83% (Thermopolis), 85% (Berlin), ~99% (Eichstatt), ~100% (Munich), 100% (London), 104% (Solnhofen) and ~105% (Maxberg), so would seem to distinguish the Berlin+Thermopolis specimens, as opposed to the Solnhofen specimen (contra Elzanowski, 2001). Ratios in Velociraptor are more variable (103-129%), showing this could be intraspecific variation. Pedal digit IV has four phalanges in the Solnhofen specimen (as in the Didactylornis type), but five phalanges in the Berlin, Eichstatt, Munich and Thermopolis specimens. This leads to the fourth digit being shorter in the Solnhofen specimen. Though the London specimen has an unknown number of phalanges in digit IV, it is long as in specimens with five phalanges. Pedal ungual IV is longer than phalanx IV-1 in the Solnhofen specimen, but not the Berlin, Eichstatt, Munich and Thermopolis specimens. Pedal ungual IV of the Solnhofen specimen is also distinct from the London, Berlin, Eichstatt, Munich and Thermopolis specimens in being straight ventrally. Variation in pedal ungual curvature has been reported in Deinonychus too (Ostrom, 1969). Pedal flexor tubercles are large in the London (I, II, III and IV) and Solnhofen (I and III but not IV) specimens, but small (though not absent) in the Berlin, Eichstatt, Munich and Thermopolis specimens. If Zhongornis is a juvenile Confuciusornis, it would provide an example of young specimens having smaller pedal flexor tubercles than adults.
When the characters above are entered into a matrix with Shenzhouraptor and Anchiornis as outgroups to establish polarity, the London specimen branches off first due to several unique characters (scapulocoracoid fused; coracoid medially notched; ilium dorsally concave; obturator foramen in ischium; proximoventral ischial edge convex; obturator process not flaring ventrally). The other specimens are weakly united based on a triangular proximodorsal ischial process and weak pedal ungual flexor tubercles (reversed in the Solnhofen specimen and perhaps ontogenetic). Within this group, the Munich specimen is outside another clade weakly united by a small proximodorsal ischial process and a prominent distodorsal process. The only resolution within this clade is the pairing of the Maxberg and Solnhofen specimens based on metatarsal fusion, which is easily explained by ontogeny. While the Solnhofen specimen is distinct from most others (except perhaps the Maxberg specimen) due to several characters (manual phalanges III-1 and III-2 sutured; preacetabular process short; four phalanges in pedal digit IV; pedal ungual IV longer than IV-1; pedal ungual IV straight ventrally), it is also deeply nested within Archaeopteryx. The Eichstatt and Munich specimens each exhibit a single unique character (no caudal neural spines and tall posterior dorsal neural spines respectively), while the Thermopolis specimen has two (six sacral vertebrae; no obturator fossa in ischium). Thus there seems to be no support for a monophyletic Archaeopteryx excluding Wellnhoferia, so Wellnhoferia can be sunk into Archaeopteryx. The separation of the London specimen as A. lithographica from the rest as A. seimensii (or a poorly supported A. bavarica split from A. seimensii) is possible. The resulting impression is that while individual Archaeopteryx specimens (particularily the London and Solnhofen specimens) can have several unique features, there is little evidence to subdivide the genus into species containing more than one individual. The choices are similar to that entertained for Microraptor on this site, either several species each represented by a single specimen, or one species which is variable in morphology. The latter more conservative approach is taken here, especially considering the fact no specimens are adult.
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Ornithurae Haeckel, 1866
Definition- (Passer domesticus <- Archaeopteryx lithographica) (Sereno, in press; modified from Gauthier, 1986)
Other definitions- (Hesperornis regalis + Passer domesticus) (modified from Padian et al., 1999; modified from Chiappe, 1991)
(tail shorter than the femur and with an upturned and ploughshare-shaped compressed pygostyle in the adult, composed of less than six segments, and shorter than the less than eight free caudals homologous with Vultur gryphus) (Gauthier and de Queiroz, 2001)
(Hesperornis regalis + Ichthyornis dispar + Passer domesticus) (modified from Padian, 2004)
= Orthavialae Ji, Ji, Zhang, You, Zhang, Wang, Yuan and Ji, 2002
Diagnosis- nasal process of premaxilla over 50% of snout length (also in oviraptoriforms and Epidexipteryx); dorsal centra much longer than wide (also in many non-paravians and Anchiornis; absent in Jixiangornis, Sapeornis, Alethoalaornis, Eoalulavis, Archaeorhynchus and Patagopteryx); scapula tapers distally (also in Deinocheirus, Nothronychus and Bambiraptor; absent in Confuciusornithidae, Songlingornis(?) and Hesperornis); scapula and coracoid articulate at <90 degree angle (absent in Hesperornithes and Ratites); strut-like coracoid (absent in Confuciusornis zhengi and Hesperornithes); acrocoracoid process (absent in Jixiangornis and Hesperornis); forelimb (humerus + ulna) over 110% of hindlimb (femur + tibiotarsus) (also in Rahonavis; absent in Yandangornis, Dalianraptor, Confuciusornithidae, many enantiornithines and many ornithuromorphs more derived than Archaeorhynchus); ulna over 97% length of humerus (absent in Jixiangornis, Dalianraptor, Confuciusornithidae, Elsornis, Patagopterygiformes and basal Carinatae); semilunate carpal fused to metacarpals II and III (also in Anchiornis; not in Jixiangornis); semilunate carpal covers less than half of proximal edge of metacarpal I (also in Anchiornis; absent in Jixiangornis, Dalianraptor and Zhongjianornis); manual phalanx II-1 with posterior flange (also in Microraptoria; absent in "Cathayornis" chabuensis); opisthopubic pelvis (also in Parvicursorinae, some troodontids and Microraptoria + Eudromaeosauria); antitrochanter located posterodorsal to acetabulum (absent in Patagopteryx and Yixianornis); trochanteric crest on femur (also in Parvicursorinae, derived troodontids and Rahonavis); Ectocondylar tuber forms single articular surface with lateral condyle of femur (also in Deinonychus and Anchiornis; absent in Zhongornis, Shanweiniao and Alamitornis- ontogenetic?); laterally projected fibular trochlea on femur (also in Alvarezsauridae, Protarchaeopteryx, Rahonavis and Unenlagia); distal tarsals fused to metatarsus (also in Patagonykus, Microraptor and Velociraptor).

undescribed ornithurine (Sanz, Chiappe, Fernadez-Jalvo, Ortega, Sanchez-Chillon, Poyato-Ariza and Perez-Moreno, 2001)
Late Barremian, Early Cretaceous
Calizas de La Huerguina Formation, Spain
Material- (LH 11386 bird 4) (juvenile) femur, tibia, metatarsal I, phalanx I-1, pedal ungual I, metatarsus, phalanx III-3, phalanx IV-3
Comments- This specimen is one of the two most fragmentary of four juvenile birds found associated in a theropod or pterosaur pellet. It was only identified as a bird by Sanz et al. (2001), and is the specimen on the left which is colored black in their illustration. The curved metatarsal I and elongate digit I are similar to ornithurines (sensu Gauthier), but its relationships cannot be determined further without better description or illustration.
Reference- Sanz, Chiappe, Fernadez-Jalvo, Ortega, Sanchez-Chillon, Poyato-Ariza and Perez-Moreno, 2001. An Early Cretaceous pellet. Nature. 409, 998-999.

Jeholornithiformes Zhou and Zhang, 2006
Jeholornithidae Zhou and Zhang, 2006
Comments- Zhou and Zhang erected both of these taxa to include only Shenzhouraptor (which they viewed as a synonym of Jeholornis, in addition to Jixiangornis). If Jixiangornis, Dalianraptor or another taxon is found to be more closely related to Shenzhouraptor than to Aves, then they may become useful.
Reference- Zhou and Zhang, 2006. Mesozoic birds of China- A synoptic review. Vertebrata PalAsiatica. 44(1), 60-98.
Shenzhouraptor Ji, Ji, You, Zhang, Yuan, Ji, Li and Li, 2002
= Jeholornis Zhou and Zhang, 2002
S. sinensis Ji, Ji, You, Zhang, Yuan, Ji, Li and Li, 2002
= Jeholornis prima Zhou and Zhang, 2002
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (LPM 0193) (subadult) partial skull, incomplete mandible, five or six cervical vertebrae, ten to twelve dorsal vertebrae, dorsal ribs, uncinate processes, three sacral vertebrae, (caudal series ~320 mm) twenty-three to twenty-five caudal vertebrae, chevrons, scapulae (one incomplete; ~48 mm), partial coracoid, furcula, partial sternal plate, humeri (79.8 mm), radius, ulnae (83.4 mm), radiale, ulnare, semilunate carpal, metacarpal I + phalanx I-1 (30 mm), manual ungual I, metacarpal II (36.7 mm), phalanx II-1 (17.8 mm), phalanx II-2 (19.2 mm), manual ungual II (13.9 mm on curve), metacarpal III (36.6 mm), phalanx III-1, phalanx III-2, phalanx III-3, manual ungual III, ilia (one fragmentary; ~40.8 mm), pubes (one partial; ~56.4 mm), incomplete ischium, femora (55.4 mm), tibiae (68.3 mm), metatarsal I (7.8 mm), phalanx I-1 (9 mm), pedal ungual I (12.1 mm on curve) , metatarsals II (29.8 mm), phalanx II-1 (9 mm), phalanx II-2 (10.5 mm), pedal ungual II, metatarsals III (34.6 mm), phalanx III-1 (10.9 mm), phalanx III-2 (10.6 mm), phalanx III-3 (7.3 mm), pedal ungual III, metatarsals IV (31.8 mm), phalanx IV-1 (8.2 mm), phalanx IV-2 (6.7 mm), phalanx IV-3 (6.2 mm), phalanx IV-4, pedal ungual IV, remiges (to 210 mm), retrices
Referred- (IVPP V13274; holotype of Jeholornis prima) (one year old) skull, mandibles, hyoids, five cervical vertebrae, seven dorsal vertebrae, dorsal ribs, gastralia, sixth sacral vertebra, twenty-two caudal vertebrae, twenty chevrons, incomplete scapula, coracoids, partial furcula, partial sternal plate, posterolateral sternal process, humeri (110 mm), radii, ulnae (109 mm), ulnare, metacarpals I, phalanx I-1, manual unguals I, carpometacarpus (one incomplete; 47 mm), phalanges II-1, phalanges II-2, manual unguals II, phalanx III-1, phalanx III-2, phalanges III-3, manual unguals III, ilium, pubes (64 mm), incomplete ischium, femora (one partial; 75 mm), tibiae (88 mm), partial fibula, astragali, calcaneum, pedal ungual I, proximal metatarsus (~47 mm), phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, eight pedal phalanges, five pedal unguals, metatarsal V, stomach contents (Zhou and Zhang, 2002)
(IVPP V13550) (subadult) skull, mandible, about ten cervical vertebrae, about thirteen dorsal vertebrae, partial dorsal ribs, sixth sacral vertebra, twenty-seven caudal vertebrae, chevrons, ilia, pubis, ischium, femora, tibiae, metatarsal I, phalanges I-1, pedal unguals I, metatarsals II, phalanges II-1, phalanges II-2, pedal unguals II, metatarsals III, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, metatarsals IV, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, retrices (Zhou and Zhang, 2003)
(IVPP V13553) (subadult) (less than one year old) skull, cervical vertebrae, dorsal vertebrae, dorsal ribs, sacrum, twenty-four caudal vertebrae, scapulae, partial coracoid, furcula, humeri (94 mm), radii, ulnae (96 mm), metacarpal II (45 mm), phalanx II-1, phalanx II-2, metacarpal III, phalanx III, ilia, pubes, femora (62 mm), tibiae (68 mm), distal tarsal, metatarsal I, phalanx I-1, pedal ungual I, metatarsals II, phalanges II-1, phalanges II-2, pedal unguals II, metatarsals III (40 mm), phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, metatarsals IV, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, remiges (Zhou and Zhang, 2003)
Diagnosis- (after Ji et al., 2002) ratio of forelimb (humerus plus ulna plus carpometacarpus) to hindlimb (femur plus tibiotarsus plus tarsometatarsus) between 1.2 and 1.3.
(modified after Zhou and Zhang, 2002) lacrimal with two vertical and elongated pneumatic fossae; dentary symphysis fused (also in Confuciusornithidae, Gobipteryx, Apsaravis and Aves); manual phalanx III-2 <60% of the length of III-1 (also in some dromaeosaurids); manual phalanges III-1 and III-2 articulate to be medially concave; fenestra in distal end of posterolateral sternal process.
(after Zhou and Zhang, 2006) premaxilla toothless (also in Jixiangornis, Yandangornis, Zhongjianornis, Confuciusornithidae and Aves).
(proposed) jugal dorsal process angled anteriorly; chevrons contact at distal tips; scapula and coracoid with mobile articulation (also in Rahonavis, Jixiangornis and Ornithothoraces); coracoid with concave articulation with scapula (also in Jixiangornis and Ornithuromorpha).
Other diagnoses- Ji et al. (2002) included other characters in their diagnosis. Jixiangornis has a comparable number of caudal vertebrae, and almost all deinonychosaurs and basal avialans have distal caudal centra 3-4 times longer than tall. Robust, well developed forelimbs and a broad manual phalanx II-1 could be said to be present in most ornithurines (sensu Gauthier). The deltopectoral crest is identical in length in Jixiangornis. The remiges exceed ulnar+manual length in confuciusornithids and enantiornithines (e.g. Eoenantiornis) as well, so is probably an ornithurine character.
Zhou and Zhang (2002) also included additional characters in their diagnosis. Robust mandibles are also present in Jixiangornis, Dalianraptor and confuciusornithids. The number of caudal vertebrae behind the transition point varies between twenty and twenty-two (Zhou and Zhang, 2003), which is comparable to some other basal paravians like Scansoriopteryx, Microraptor and Sinusonasus.
Zhou and Zhang (2003) added a couple problematic characters. Teeth are not absent, but are present in the dentary. The U-shaped furcula is shared with other basal paravians.
Comments- While Zhou and Zhang (2002) claimed the tail has "unexpected elongated prezygopophyses and chevrons, resembling that of dromaeosaurids", they are actually far shorter than most dromaeosaurids and resemble generalized paravians such as Scansoriopteryx, troodontids and Mahakala instead.
Jeholornis- Both Shenzhouraptor and Jeholornis were named in July 2002, with Shenzhouraptor appearing in the July issue of Geological Bulletin of China, and Jeholornis appearing in the July 25th issue of Nature. I first recognized them as synonymous on the DML, which has been the consensus in the literature as well. Ji et al. (2003) made Jeholornis a junior synonym of Shenzhouraptor without comment, incorrectly making the Jeholornis holotype a paratype of Shenzhouraptor. Zhou and Zhang (2006) on the other hand, made Shenzhouraptor a junior synonym of Jeholornis, again without discussion. They stated the ICZN gives priority to a weekly journal instead of a monthly journal, undoubtedly based on Article 21.3.1. Yet, that article only applies in the absence of evidence of "the earliest day on which the work is demonstrated to be in existence as a published work." As Olshevsky (DML, 2002) noted, Wang (2002) reported the Shenzhouraptor article was published as early as July 23rd, two days before Jeholornis was published. Thus Shenzhouraptor has precedence if the genera are synonymous. Somewhat oddly, no one has yet published a rationale for their synonymy.
Comparison is hindered by the short description of each taxon and low resolution photos for much of Jeholornis. Shenzhouraptor's holotype was reported to have no observed teeth, yet the Jeholornis holotype has three tiny dentary teeth, and IVPP V13550 has two. I agree with Chiappe and Dyke (2006) that poor preservation in Shenzhouraptor may be to blame, as they are hard to discern even in the published photo of Jeholornis. Ji et al. report that Shenzhouraptor has a straight mandible, and its lower edge does appear less concave than in Jeholornis and IVPP V13550, but this could be due to individual variation. The caudal vertebral count of Shenzhouraptor was reported as 23-25, which is within the range of individual variation of the Jeholornis holotype (22), IVPP V13553 (24) and V13550 (27). The decreasing count with size/age is congruent with trends seen in other basal avialans. There seems to be a deeper dorsal concavity just posterior to the acromion in Shenzhouraptor than the referred Jeholornis specimen IVPP V13553, but this is poorly preserved in the Jeholornis holotype. The first metacarpal and phalanx I-1 in Shenzhouraptor have an "unclear" suture, while that in the Jeholornis holotype is obvious. Whether Shenzhouraptor's condition is anatomical or taphonomic is uncertain. Phalanx II-2 is 108% of II-1 in Shenzhouraptor, but 92% in IVPP V13553 and ~96% in Jeholornis. Yet this is known to vary by 28% in Deinonychus and over 80% in Struthiomimus and Dromiceiomimus. The third manual digit would seem to differ in the ratio between phalanges III-2 and III-1 based on the illustration of Shenzhouraptor, which has a ratio of ~80% compared to Jeholornis' reported ratio of <50%. Yet the photo of Shenzhouraptor's manus suggests an alternative identification where the supposed proximal end of III-2 is really the distal end of III-1, based on apparent distal condyles and phalanx outlines. Indeed, Ji et al. only dotted in the boundary in their illustration, and the resulting ratio of ~50% matches the ~40% ratio measured in Jeholornis. The manus is otherwise extremely similar in the two holotypes, except that in Jeholornis metacarpal III reaches slightly past metacarpal II. The ilia seem to differ in that Shenzhouraptor's has a large ventral process on the preacetabular process while Jeholornis' tapers based on the illustration. Yet IVPP V13553 has an ilium in medial view which seems to taper as well, unless the ventral process is taken into account, which is separated from the main blade by the cuppedicus fossa. In the Jeholornis holotype, the photo indicates that the ilium is overlain by the caudal series, so is probably in medial view as well. The ventral process would be underneath the second and third caudals and chevrons if it exists, so this difference cannot be substantiated. IVPP V13553 differs from both holotypes in having a postacetabular process which is blunt posteriorly. The proximodorsal ischial process in Jeholornis' holotype is expanded distally, while Shenzhouraptor's is rounded. Perhaps more importantly, the ischium of Jeholornis is illustrated with a pronounced dorsal kink about halfway down the shaft, inviting comparisons to the mid dorsal processes of some other maniraptorans. Shenzhouraptor's is gently concave. Examination of the photo indicates that the ischium in Jeholornis is straight until a crack in the slab interrupts it, after which what must have been identified as the distal ischium extends at a more ventral angle. Yet this supposed distal ischium is just as parsimoniously a fibular fragment, while the true distal ischium could be underneath the left tibiotarsus or right femur. The proximal metatarsus of Shenzhouraptor is unfused, unlike the Jeholornis holotype, but this could be ontogenetic due to its smaller size. Similarly, the small IVPP V13553 has a free distal tarsal and seems to have an unfused metatarsus. Shenzhouraptor was reported to have an unreversed hallux, while Jeholornis' was said to be reversed. Yet in Jeholornis the distal metatarsus is almost completely destroyed by a gap in the matrix, all phalanges except for right digit IV are disarticulated, and the probable hallucial ungual (based on its proximal position) is oriented to curve in the same direction as five of the six other pedal unguals in any case. IVPP V13550 has a hallux preserved in unreversed position like the Shenzhouraptor holotype, while Li and Zhang (2008) find the preserved orientation depends on taphonomy in any case. In conclusion, the demonstrable differences are limited to those explainable by ontogeny (caudal count; metatarsal fusion) or individual variation (degree of ventral dentary concavity; distal extent of metacarpal III; manual digit II proportions; proximodorsal ischial process expansion). Their synonymy is upheld.
References- Ji, Ji, You, Zhang, Yuan, Ji, Li and Li, 2002. Discovery of an Avialae bird - Shenzhouraptor sinensis gen. et sp. nov. - from China. Geological Bulletin of China. 21(7), 363-369.
Mortimer, DML 2002. http://dml.cmnh.org/2002Jul/msg00671.html
Olshevsky, DML 2002. http://dml.cmnh.org/2002Nov/msg00292.html
Wang, 2002. Fossil supports dinosaur-into-bird theory. China Daily. 07/23/2002.
Zhou and Zhang, 2002. A long-tailed, seed-eating bird from the Early Cretaceous of China. Nature. 418, 405-409.
Ji, Ji, You, Zhang, Zhang, Zhang, Yuan and Ji, 2003. An Early Cretaceous avialan bird, Shenzhouraptor sinensis from Western Liaoning, China. Acta Geologica Sinica. 77(1), 21-27.
Zhou and Zhang, 2003. Jeholornis compared to Archaeopteryx, with a new understanding of the earliest avian evolution. Naturwissenschaften. 90, 220-225.
Chiappe and Dyke, 2006. The early evolutionary history of birds. J. Paleont. Soc. Korea. 22(1), 133-151.
Zhou and Zhang, 2006. Mesozoic birds of China- A synoptic review. Vertebrata PalAsiatica. 44(1), 60-98.
Li and Zhang, 2008. Reconstructing the habits of Jeholornis prima. SAPE 2008 abstracts. 11.
Erickson, Rauhut, Zhou, Turner, Inouye, Hu and Norell, 2009. Was dinosaurian physiology inherited by birds? Reconciling slow growth in Archaeopteryx. PLoS ONE. 4(10), e7390. doi:10.1371/journal.pone.0007390

Euavialae Ji, Ji, Zhang, You, Zhang, Wang, Yuan and Ji, 2002
Diagnosis- dorsal premaxillary process extends to anterior edge of orbit (unknown in Shenzhouraptor; absent in most enantiornithines and Archaeorhynchus); quadrate not pneumatic (also in Epidexipteryx, Dromaeosauridae and many other taxa; absent in Patagopteryx, Ichthyornis and Aves); dentary strongly forked posteriorly (also in oviraptorosaurs and Epidexipteryx; absent in most ornithothoracines); at least seven sacral vertebrae (also in Parvicursorinae, some caenagnathoids and Epidexipteryx); less than twenty-three caudal vertebrae (also in Caudipteryx, Epidexipteryx and some Archaeopteryx specimens; absent in Jixiangornis and Yandangornis); pygostyle (also in Beipiaosaurus, Similicaudipteryx and Nomingia; absent in Jixiangornis and Yandangornis); humeral distal condyles developed on anterior surface (also in Sinosauropteryx, Therizinosauria, Alvarezsauridae and Bambiraptor); brevis fossa absent on ilium (also in some therizinosaurids; absent in Patagopteryx); astragalocalcaneum fused to tibia (also in derived alvarezsaurids, Pedopenna and Microraptor; absent in Vorona, Paraprotopteryx, Hebeiornis and Gobipteryx- ontogenetic?).
Comments- This name was used in a figure by Ji et al. (2002) for a clade containing Jixiangornis and Pygostylia, but not Shenzhouraptor or Archaeopteryx.
While it seems logical that the long-tailed, pygostyle-less Jixiangornis, Yandangornis and Dalianraptor are more basal than omnivoropterygids, the total character evidence may suggest otherwise. For instance, Jixiangornis and Dalianraptor have narrower interclavicular angles like ornithothoracines. Jixiangornis has a mobile scapulocoracoid (as in Shenzhouraptor and ornithothoracines). Yandangornis has posterolateral sternal processes which extend posteriorly to level of the median sternal edge, as in most ornithothoracines. None of these characters are found in omnivoropterygids or confuciusornithids.
The posteriorly extensive dorsal premaxillary processes were reported as absent in Sapeornis and Zhongjianornis, but my examination of figures suggests they were misidentified as nasals.
References- Ji, Ji, Zhang, You, Zhang, Wang, Yuan and Ji, 2002. A new avialian bird - Jixiangornis orientalis gen. et sp. nov. - from the Lower Cretaceous of Western Liaoning, NE China. Journal of Nanjing University (Natural Sciences). 38(6), 723-736.

unnamed euavialan (Molnar, 1999)
Albian, Early Cretaceous
Griman Creek Formation, New South Wales, Australia
Material- (AM F102786) distal tibiotarsus (7.2 mm wide)
(AM F102787) distal tibiotarsus (7.6 mm wide)
(QM F37912) distal tibiotarsus (26.7 mm wide)
Comments- Molnar (1999) suggested this was a non-enantiornithine, non-ornithuromorph ornithothoracine. The lack of a fibular articulation is similar to ornithurines and the complete fusion suggests a euavialan. The lack of a supratendinal bridge excludes it from Ornithurae sensu Chiappe. The small medial condyle excludes it from Enantiornithes, though taxa such as Yandangornis and the basal ornithuromorph PKUP 1069 are similar. The distally rounded condyles are also unlike all but the most basal enantiornithines. The lack of any proximal extent to the articular surface posteriorly is unlike pygostylians. These are thus most parsimoniously from a non-pygostylian euavialan.
Reference- Molnar, 1999. Avian tibiotarsi from the Early Cretaceous of Lightning Ridge, N.S.W. In Tomida, Rich and Rich (eds). Proceedings of the Second Gondwanan Dinosaur Symposium, National Sciences Museum Monographs. 15, 197-209.

Jixiangornis Ji, Ji, Zhang, You, Zhang, Wang, Yuan and Ji, 2002
J. orientalis Ji, Ji, Zhang, You, Zhang, Wang, Yuan and Ji, 2002
Late Barremian-Early Aptian, Early Cretaceous
Jianshangou Beds of Yixian Formation, Liaoning, China
Holotype- (CDPC-02-04-001) skull (80.7 mm), mandibles, hyoid, nine cervical vertebrae (12.5, 13.3, 14.8 mm), eight dorsal vertebrae (8-9 mm), eight pairs of dorsal ribs, uncinate processes, thirteen to fourteen rows of gastralia, sacrum (43 mm), twenty-seven caudal vertebrae (sixth caudal vertebra 18.6 mm, seventh caudal vertebra 20.7 mm, eighth caudal vertebra 21.2 mm, ninth caudal vertebra 22.4 mm), chevrons, partial scapula, coracoids (39.5, 40.6 mm), furcula, incomplete sternum, four to five sternal ribs, humeri (112 mm), radii (one partial; 103.4 mm), ulnae (one partial; 107.1 mm), radiale, semilunate carpal, metacarpal I (11.3 mm), phalanx I-1 (28 mm), manual ungual I, metacarpal II (44.9 mm), phalanx II-1 (22.7 mm), phalanx II-2 (21.1 mm), manual ungual II (18.5 mm), metacarpal III (47.2 mm), phalanx III-3 (12.3 mm), manual ungual III (10.2 mm), ilium (28 mm), pubes (36.6 mm), ischium, femora (71.9 mm), tibiotarsi (83.2, 83 mm), fibulae (67.7, 55.6 mm), metatarsals I (10.5, 9.2 mm), phalanges I-1 (9.3 mm), pedal unguals I (15.6, 14.1 mm), tarsometatarsus (II 38.7 mm, III 41.3 mm, IV 39.8 mm), phalanges II-1 (9.3 mm), phalanges II-2 (13.7, 12.9 mm), pedal unguals II (23.4 mm), phalanges III-1, phalanges III-2, (11.9, 12.6 mm), phalanges III-3 (12.9, 12.2 mm), pedal unguals III (19.4 mm), phalanges IV-1 (9.4 mm), phalanges IV-2 (7.9, 8.5 mm), phalanges IV-3 (6.8, 7 mm), phalanges IV-4 (10.5, 10.5 mm), pedal unguals IV (16.1 mm)
Referred- specimen including posterior cervical vertebrae, dorsal ribs, scapulae, coracoids, furcula and humeri (Nesbitt et al., 2009)
Diagnosis- (proposed) premaxillae toothless (also in Shenzhouraptor, Yandangornis, Zhongjianornis and Confuciusornithidae); dentary toothless (also in Omnivoropterygidae, Zhongjianornis and Confuciusornithidae); posteriorly forked dentary; partially heterocoelous dorsal series(?); dorsal parapophyses centrally placed(?); some proximal chevrons fused to centra(?); laterally curved acromion process(?); procoracoid process; coracoid pneumatic(?); low interclavicular angle (50-60 degrees); middle of furcular rami expanded; strongly compressed distal humerus(?).
Comments- The description of Jixiangornis has yet to be translated from Chinese, and the photos are only available as photocopies. The skull, pectoral area, manus and pes were illustrated, though somewhat schematically, and unpublished small color photos of the skeleton are also available online. Yuan (2005) coded Jixiangornis for Clarke's bird matrix, providing much additional anatomical information. Most recently, Nesbitt et al. (2009) included a good quality photograph of the pectoral area for their theropod furcula paper, as well as a description of the furcula. Confusingly, this photo does not correspond to the holotype, though it is labeled as such. Differences include the disarticulation of one humerus, angle of the other, the fact the cervical series angles to the right, the furcula with an apex pointing anteriorly, the scapula on the right being oriented transversely, and the coracoids being nearly parallel. Notably, some of these are verifiable as being different from photographs of the holotype, not just the illustrations. Yet the furcular morphology is identical, featuring the low interclavicular angle and expanded rami characteristic of the taxon. This therefore must be a referred specimen.
Zhou and Zhang (2006) synonymized Jixiangornis with Jeholornis and Shenzhouraptor, merely stating it "possesses no obvious difference". The limited information makes comparison difficult. The skull is crushed with some questionable identifications. Two fenestrae are identified as the external naris, with a third elongate fenestra existing posteroventral to these. It is likely the premaxillary and nasal processes disarticulated and deformed to cause this illusion. As illustrated, the orbit is very small and dorsally placed, with a large posterior antorbital fenestra placed almost entirely ventral to it, and even extending posteriorly under part of the orbit. This is quite unlike any theropod and is near certainly a misinterpretation. More likely, the supposed posterior antorbital fenestra is the anteroventral portion of the orbit, and the anterior antorbital fenestra is the real antorbital fenestra. This would make the lacrimal be the thinner portion anteroventral to its label, while the labeled jugal is probably a braincase or palatal element. The more vertical process ventral to the labeled jugal may then be the actual jugal. The dentary is posteriorly forked, unlike Shenzhouraptor, but similar to confuciusornithids and perhaps omnivoropterygids. Yuan codes the cervicals as being amphicoelous, as opposed to the semiheterocoelous centra in Shenzhouraptor. On the other hand, he codes the dorsal vertebrae as being at least partially heterocoelous, which is otherwise unknown except in some ornithuromorphs. The dorsals are also coded as having centrally placed parapophyses, unlike Shenzhouraptor, but similar to derived enantiornithines. Another difference in dorsal vertebrae is that the centra are coded as being markedly longer than wide. The sacrum is coded as having eight vertebrae, like derived enantiornithines and ornithuromorphs, but unlike the six in Shenzhouraptor. However, the Chinese description has a "7" in the sacral paragraph, which suggests the presence of only seven centra. While Yuan codes Shenzhouraptor as differing in having less caudal vertebrae, some specimens (IVPP V13550) have twenty-seven caudals as in Jixiangornis. Unlike Shenzhouraptor, the proximal caudal vertebrae are coded as having transverse processes shorter than centrum width. The proximal chevrons are coded as being fused to their centra, unlike most other Mesozoic birds. The acromion process is coded as being laterally curved in Jixiangornis, unlike Shenzhouraptor. Yuan codes the scapulocoracoid as differing from Shenzhouraptor in being unfused, but Shenzhouraptor has an unfused pectoral girdle as well. He also codes them as differing due to Jixiangornis' procoracoid process, but this may merely be hidden in Shenzhouraptor specimens (under the furcula in the Jeholornis holotype; under the scapula in IVPP V13553). Contra Yuan's coding, Shenzhouraptor lacks a laterally concave coracoid, so does not differ from Jixiangornis in this feature. Yuan codes Jixiangornis as having a pneumatic coracoid, which would be almost unique among Mesozoic theropods. Jixiangornis has less of a lateral coracoid process than Shenzhouraptor and the glenoid extends proximally to the apex of the coracoid, whereas in Shenzhouraptor there is a proximally projecting acromion. The interclavicular angle is lower (50-60 degrees) than Shenzhouraptor (70-75 degrees). It is coded as having a tubercle-sized hypocleidium, which is a character that exhibits individual variation in some other taxa. Although Yuan (2005) codes it as being laterally excavated, Nesbitt et al. (2009) disagree. Nesbitt et al. do note the furcula differs from Shenzhouraptor and is similar to oviraptorids in having rami expanded in their middle. Jixiangornis' sternum differs in being fused with a median keel and anterolaterally projecting posterolateral process bases. Ji et al. note the forelimb is longer (131% of hindlimb length) than in Shenzhouraptor (126-127%). The humerus is coded as having an anteriorly projecting deltopectoral crest in Shenzhouraptor, but the photos suggests it is dorsally projecting as in Jixiangornis. Other differing humeral codings include a strongly compressed distal end (as in some enantiornithines) and a brachial fossa. Unlike Shenzhouraptor, the semilunate carpal is unfused to the second and third metacarpals in Jixiangornis. The first manual digit is shorter in Jixiangornis, being 88% of metacarpal II length as opposed to 82%. Yuan codes manual phalanx II-1 as being strongly dorsoventrally flattened as in some ornithuromorphs, but this is untrue. He also codes Shenzhouraptor as differing in having phalanx II-2 longer than II-1, but this is only true of the holotype, not IVPP V13274 or V13553. The first manual ungual seems more robust and the third smaller and less curved in Jixiangornis, but this may be influenced by claw sheaths and illustration quality. The pelvis and hindlimb do not differ in codings, while the pes is nearly identical in morphology. While ontogeny might explain a few differences, such as sacral number, low interclavicular angle and sternal fusion, Jixiangornis is a bit smaller than the largest Shenzhouraptor specimen. Furthermore, the unfused carpometacarpus would be expected in a younger individual, not an older one. Also important is that Jixiangornis is from an earlier strata than any Shenzhouraptor specimen. The combination of evidence, despite Yuan's numerous miscodings, supports keeping Jixiangornis separate from Shenzhouraptor.
Ji et al. (2002) believed Jixiangornis was closer to modern birds than Archaeopteryx and Shenzhouraptor, but outside Pygostylia. Yuan (2005) has been the only author to include Jixiangornis in a phylogenetic analysis, where it emerged sister to Rahonavis, closer to modern birds than archaeopterygids, but further than Shenzhouraptor.
References- Ji, Ji, Zhang, You, Zhang, Wang, Yuan and Ji, 2002. A new avialian bird - Jixiangornis orientalis gen. et sp. nov. - from the Lower Cretaceous of Western Liaoning, NE China. Journal of Nanjing University (Natural Sciences). 38(6), 723-736.
Yuan, 2005. Restudy on sapeornithids from the Lower Cretaceous of Yixian County, Liaoning. PhD Thesis. China University of Geosciences. 157 pp.
Zhou and Zhang, 2006. Mesozoic birds of China- A synoptic review. Vertebrata PalAsiatica. 44(1), 60-98.
Nesbitt, Turner, Spaulding, Conrad and Norell, 2009. The theropod furcula. Journal of Morphology. DOI: 10.1002/jmor.10724

Dalianraptor Gao and Liu, 2005
D. cuhe Gao and Liu, 2005
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (D2139) (625 mm) skull, mandible, cervical vertebrae, dorsal vertebrae, dorsal ribs, less than twenty-three caudal vertebrae, scapula (30 mm), furcula, sternum, humeri (52 mm), radius (42 mm), ulnae (46 mm), carpus, metacarpals I (6 mm), phalanges I-1 (20, 21 mm), manual unguals I (20, 17 mm), metacarpals II (23 mm), phalanges II-1 (22 mm), phalanges II-2 (19, 22 mm), metacarpals III (22 mm), phalanges III-1 (5 mm), phalanges III-2 (12 mm), phalanges III-3 (13 mm), manual ungual IIIs (17, 16 mm), ilium (32 mm), femora (49 mm), tibiotarsi (68, 63), fibula (36 mm), phalanges I-1 (9 mm), pedal unguals I (12 mm), metatarsals II (24 mm), phalanges II-1 (7 mm), phalanges II-2 (7 mm), metatarsals III (43 mm), phalanges III-1 (14 mm), phalanges III-2 (11 mm), phalanges III-3 (13, 11 mm), metatarsals IV (43 mm), phalanges IV-1 (6 mm), phalanges IV-2 (8 mm), phalanges IV-3 (6 mm), phalanges IV-4 (5 mm), pedal unguals IV (10 mm), retrices
Diagnosis- (after Gao and Liu, 2005) forelimb/hindlimb ratio of .82.
Comments- This taxon's description has yet to be translated from Chinese and features low quality photographs, both of which hinder evaluation. It's quite possible other elements are preserved, such as a sacrum or coracoids, for example. The skull appears similar to Shenzhouraptor and Jixiangornis, especially in the decurved dentary with expanded symphysis and reduction of tooth number/size. The tail reportedly consists of less vertebrae than Shenzhouraptor or Archaeopteryx. The forelimb is shorter than other basal avialans and probably indicates Dalianraptor was flightless. The manus seems especially unique, with confuciusornithid-like characters (short phalanx I-1; apparently reduced second manual ungual; short phalanx III-1). However, metacarpal I is shorter (as in most other ornithurines) and the elongate tail is more plesiomorphic. Though extremely preliminary, the data suggests intriguing possibilities, such as independant development of pygostyles in confuciusornithids, and neoflightless taxa on the confuciusornithid stem. One of the only references to mention Dalianraptor since its description is Chiappe and Dyke (2006), who believe the taxon is distinct from, but related to, Shenzhouraptor.
References- Gao and Liu, 2005. A new avian taxon from Lower Cretaceous Jiufotang Formation of western Liaoning. Global Geology. 24(4), 313-316. (in Chinese).
Chiappe and Dyke, 2006. The early evolutionary history of birds. J. Paleont. Soc. Korea. 22(1), 133-151.

Yandangithformes Cai and Zhao, 1999
Yandangornithidae Cai and Zhao, 1999 emmend. Creisler, unpublished
= Yandangithidae Cai and Zhao, 1999
Comments- Cai and Zhao (1999) incorrectly formed both order and family names for Yandangornis. Creisler (DML, 2000) noted that the ICZN requires the family name to be emmended, as it was named in 1999 and thus falls under the jurisdiction of the 3rd edition (the 4th edition changed this rule). Order names are not covered by the ICZN though, so Yandangithformes must remain. Both names are presently redundant with Yandangornis, but may prove useful if Dalianraptor, Jixiangornis, Shenzhouraptor or another taxon is found to be more closely related to Yandangornis than to Aves.
References- Cai and Zhao, 1999. A long tailed bird from the Late Cretaceous of Zhejiang. Science in China (series D). 42(4), 434-441.
Creisler, DML 2000. http://dml.cmnh.org/2000Jul/msg00451.html
Yandangornis Cai and Zhao, 1999
Y. longicaudus Cai and Zhao, 1999
Santonian, Late Cretaceous
Tangshang Group, Zhejiang, China
Holotype- (Zhejiang Museum of Natural History M1326) (588 mm) skull (47 mm), mandibles, nine cervical vertebrae (80 mm), four dorsal vertebrae, dorsal ribs, gastralia, nineteen caudal vertebrae (305 mm), distal scapula, partial coracoid, partial furcula, sternum (50 mm), humeri (80 mm), proximal radii, proximal ulnae, distal phalanx II-1, phalanx II-2, manual ungual II, distal phalanx III-2, phalanx III-3, manual ungual III, pubis (41 mm), femora (106 mm), tibiotarsi (132 mm), fibula (40 mm), metatarsal I, phalanx I-1, pedal ungual I, tarsometatarsi (70 mm), phalanges II-1, phalanges II-2, pedal unguals II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV
Diagnosis- (after Cai and Zhao, 1999) premaxillae toothless (also in Shenzhouraptor, Jixiangornis, Zhongjianornis and Confuciusornithidae); sternum much longer than wide; metatarsus fused distally; pedal unguals reduced in size and curvature.
(proposed) very large premaxillae (ventral edge equals 40% of skull length); mandible less than three-fourths skull length; last cervical vertebra longer than others; sternum with broad median ventral convexity on posterior half; sternum concave posteriorly; distal femoral condyles more than twice as wide as shaft; phalanx III-1 shortest in third pedal digit.
Other diagnoses- Cai and Zhao (1999) include several other characters in their diagnosis which are symplesiomorphies (lightly built skull; gastralia present; unreduced forelimbs; humerus lacking pneumatic fossa or foramen; broad sternum; sternum with lateral processes; long and slender digits). The number of caudal vertebrae is similar to Dalianraptor.
Comments- This specimen was discovered in 1986, associated with the pterosaur Zhejiangopterus. It was illustrated in a somewhat schematic manner, with only low quality photographs. The authors refer Yandangornis to its own family (Yandangithidae) and order (Yandangithiformes) within the Sauriurae. As the Sauriurae is based on symplesiomorphies, its relationships must be reconsidered. Very few authors have mentioned Yandangornis since. Paul (2002) considered the genus to be a neoflightless ornithurine (sensu Gauthier) outside Avebrevicauda. Zhou and Zhang (2006) merely stated it showed "no diagnosis of birds" and questioned whether it was a bird-like dinosaur instead. However, numerous characters are shared with ornithurine birds including the reduced number of caudal vertebrae, fused sternum, trochanteric crest, completely fused tibiotarsus, fibla not contacting tarsus, fused metatarsus and proximal expansion of metatarsal III. Previously, Auditore (DML, 2002) reported personal communication from Zhou indicating he believed Yandangornis is synonymous with Shenzhouraptor (= Jeholornis), but this is highly unlikely given the numerous differences and later age of Yandangornis.
Description- The skull is preserved in ventral view, with the mandibles articulated. It is elongate with a pointed anterior tip and subparallel lateral edges. The premaxillae are toothless and large, even more extensive than confuciusornithids. A broad premaxillary palatal shelf seems to be present. The maxillae are also toothless and show a large antorbital fenestra. Other preserved elements include jugals, quadrates, pterygoids and the basisphenoid, although no details are discernable. The articulated (fused?) dentaries form an acute angle and end 7 mm behind the rostral premaxillary tip. The retroarticular process appears short.
The nine cervical vertebrae are amphicoelous and seem to lack ribs, probably due to poor preservation or illustration. They lengthen posteriorly from three to eleven millimeters. No details are visible regarding the preserved dorsal vertebrae (two mid-dorsals, two posterior dorsals). Dorsal ribs and gastralia are also preserved. Nineteen caudal vertebrae are preserved, with at least one missing at the tip. The centra are amphicoelous and the first five have transverse processes. Vertebrae become very slender after the fifth. There are no dromaeosaur-like elongate prezygopophyses and no pygostyle. No chevrons are preserved and are claimed to have been originally absent, though this seems implausible.
The coracoid is preserved articulated to the sternum anteriorly and is described as being "similar to other Mesozoic birds, especially the Cretaceous birds". This could suggest it was strut-like, but the figure is unclear regarding this point. The distal scapula is said to be elongate and straight. A furcular fragment is preserved, possibly the left distal end. The sternum is fused and twice as long as wide, as in derived ornithuromorphs. There are anterolateral processes, short tapered posterolateral processes, no posteromedial processes, but a short tapered posteromedian process is present. It lacks a keel, but has a median bump in the posterior half. What are illustrated as three elongate sternal ribs on either side of the sternum are more likely dorsal ribs based on their length.
The humerus is sigmoidal, with a low proximally placed deltopectoral crest and no pneumatic fossa. The distal condyles are distinct and a shallow olecranal fossa is present on the ulnar condyle. The radius is two-thirds as wide as the bowed ulna. There is a slight olecranon process. The phalanges are slender, with digit III reaching to the tip of II-2. Manual unguals are reduced.
The pubes are preserved in an opisthopubic position and taper distally in anterior view. They were not fused to the other pelvic elements. The authors state the pubis lacks an "anterior process", perhaps the anterior boot?
The femur is slender and straight, with a trochanteric crest and horizontal or slightly inclined head. There is a slight neck and no fourth trochantor or posterior trochantor. The distal end is greatly expanded. The tibia is fused to the astragalus and calcaneum. No fibular crest is visible, and the distal end is expanded more than the proximal end. The fibula is only 30% of the tibial length. The tarsometatarsus is non-arctometatarsalian, with the proximal end of metatarsal III actually wider than the distal end. Fusion is extensive, but incomplete in the distal tenth. It is elongate and slender. Metatarsal II is more robust than metatarsal IV, and is slightly shorter. Proximally, the tarsometatarsus has two shallow cotylae. Digit I is set 20% up the shaft of metatarsal II and is not preserved in a reversed orientation. The ungual, like the others, is small and almost straight. The ungual on digit II is slightly longer than the others. Digit II is not modified for predatory use in any way. Phalanx II-1 is much shorter than III-1, like most paravians. Phalanx II-2 is longer than II-1, as in some eumaniraptorans.
References- Cai and Zhao, 1999. A long tailed bird from the Late Cretaceous of Zhejiang. Science in China (series D). 42(4), 434-441.
Paul, 2002. Dinosaurs of the Air. The Johns Hopkins University Press, Baltimore. 460 pp.
Auditore, DML 2004. http://dml.cmnh.org/2004Oct/msg00268.html
Zhou and Zhang, 2006. Mesozoic birds of China- A synoptic review. Vertebrata PalAsiatica. 44(1), 60-98.

Zhongjianornis Zhou, Zhang and Li, 2009
Z. yangi Zhou, Zhang and Li, 2009
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V15900) (adult) skull (61 mm), mandibles, hyoids, six cervical vertebrae, seven dorsal vertebrae, partial dorsal ribs, three uncinate processes, partial synsacrum (~28 mm), eight caudal vertebrae, chevron, scapulae (59 mm), coracoids (36 mm), partial furcula, sternal plate, humeri (71 mm), radii (~73 mm), ulnae (74 mm), ulnares, metacarpals I (8 mm), phalanges I-1 (15 mm), manual unguals I, carpometacarpi (34 mm; mcII 31 mm), phalanges II-1 (18 mm), phalanges II-2 (19.5 mm), manual unguals II, phalanx III-1, ilia (39 mm), incomplete pubes, ischium, femora (46.5, 48 mm), tibiotarsi (~65, 71 mm), fibula (53 mm), metatarsal I (6 mm), phalanges I-1 (5 mm), pedal unguals I, tarsometatarsi (~29 mm; mtII 26, mtIII ~28, mtIV ~29 mm), phalanges II-1 (6.5 mm), phalanges II-2 (8 mm), pedal unguals II (11 mm), phalanges III-1 (6.5 mm), phalanges III-2 (~7 mm), phalanges III-3 (~7 mm), pedal unguals III (12 mm), phalanges IV-1 (7 mm), phalanges IV-2 (5 mm), phalanges IV-3 (~4 mm), phalanges IV-4 (6.5 mm), pedal unguals IV, feathers
Diagnosis- (after Zhou et al., 2009) sharply pointed premaxilla (also in Confuciusornithidae); premaxillae toothless (also in Shenzhouraptor, Jixiangornis, Yandangornis and Confuciusornithidae); maxilla toothless (also in Shenzhouraptor, Jixiangornis, Yandangornis and Confuciusornithidae); dentary toothless (also in Omnivoropterygidae, Zhongjianornis and Confuciusornithidae); manual ungual I small and weakly curved; metatarsal IV longer than metatarsal III.
(proposed) enlarged premaxilla; dorsal maxillary process absent; mandible sigmoidal such that dentary is dorsally convex and surangular is dorsally concave (also in some Sapeornis specimens); caudal centra procoelous (also in Confuciusornis zhengi); caudal zygapophyses non-contacting; proximal and distal humeral ends not twisted; moderately developed humeral bicipital crest (also in Archaeopteryx and Sapeornis); distal humerus highly compressed anteroposteriorly (also in Jixiangornis); dorsal ulnar cotyla not convex; dorsal ulnar condyle semilunate (also in Anchiornis and Confuciusornis zhengi); dorsal trochlear surface of ulnar dorsal condyle extends proximally an amount equal to its width; manual digit I reduced to extend to end of metacarpal II (also in Jixiangornis); metacarpal III extends distally past II (also in scansoriopterygids and some Shenzhouraptor specimens); ilial postacetabular process not less than half as deep as preacetabular process (also in Anchiornis); posterolateral ridge on femur extending proximally from lateral condyle; ginglymoid metatarsal II (also in Scansoriopteryx); metatarsal II trochlea much wider than III or IV; metatarsal IV reduced in width (also in Archaeopteryx); metatarsal V absent (also in Zhongornis?).
Other diagnoses- Zhou et al. (2009) included several other characters in their diagnosis. The tall deltopectoral crest (270% of shaft width) is also found in omnivoropterygids and confuciusornithids. The length of the crest varies strongly between humeri (36-44% of humeral length), is overlapped by Shenzhouraptor and confuciusornithids and closely approached by other basal avialans. Manual ungual II is equally small in Dalianraptor, Yandangornis and confuciusornithids, while manual ungual III is unknown (if present), leaving only the size of manual ungual I to be diagnostic.
Comments- Zhou et al. (2009) included Zhongjianornis in a version of Clarke's matrix and found it to be outside Pygostylia, but more closely related to it than Sapeornis or Shenzhouraptor. In my analyses it has an unstable position within Euavialae, but is generally not in Avebrevicauda.
Reference- Zhou, Zhang and Li, 2009. A new Lower Cretaceous bird from China and tooth reduction in early avian evolution. Proceedings of the Royal Society B. doi:10.1098/rspb.2009.0885

Cerebavis Kurochkin, Saveliev, Postnov, Pervushov and Popov, 2006
C. cenomanica Kurochkin, Saveliev, Postnov, Pervushov and Popov, 2006
Middle Cenomanian, Late Cretaceous
Melovatskaya Formation, Russia
Holotype- (PIN 5028/2) (~80-160 g) mesethmoid, parabasisphenoid, endocranial mold
Diagnosis- (after Kurochkin et al., 2006) cerebral hemispheres rounded oval; olfactory tracts thick, with large olfactory bulbs; interhemispheric fissure shallow; parietal organ well pronounced, located in pineal recess on caudal slope of interhemispheric fissure; roof of midbrain with large auditory tubercles; well-developed epiphysis (glandula pinealis) located between auditory tubercles; optic tubercles (lobi optici) located caudoventral to cerebral hemispheres, not projecting laterally beyond them; middle part of parasphenoid rostrum swollen.
Reference- Kurochkin, Saveliev, Postnov, Pervushov and Popov, 2006. On the Brain of a Primitive Bird from the Upper Cretaceous of European Russia. Paleontological Journal. 40(6), 655–667.

Avebrevicauda Paul, 2002
Definition- (ten or fewer free caudals homologous with Passer domesticus) (modified from Paul, 2002)
= Pygostylia sensu Gauthier and de Queiroz, 2001
Definition- (fused distal caudal vertebrae homologous with Vultur gryphus)

undescribed avebrevicaudan (Sanz, Chiappe, Fernadez-Jalvo, Ortega, Sanchez-Chillon, Poyato-Ariza and Perez-Moreno, 2001)
Late Barremian, Early Cretaceous
Calizas de La Huerguina Formation, Spain
Material- (LH 11386 bird 2) (juvenile) sacrum, seven caudal vertebrae, pygostyle, incomplete ilium, femora (one distal), tibia, astragalus, metatarsal II, metatarsal III, phalanx III-1, phalanges III-2, phalanges III-3, pedal ungual III, metatarsal IV, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV
Comments- This specimen is the second most complete of four juvenile birds found associated in a theropod or pterosaur pellet. It was only identified as a bird by Sanz et al. (2001), and colored light gray in their illustration. The pygostyle indicates this is an avebrevicaudan, while the length of the pygostyle (over twelve centra long) excludes ornithuromorphs from consideration. The medial tibiotarsal condyle being wider than the lateral one is only seen in Patagopteryx among ornithuromorphs. Also, the proximal end of metatarsal III is in the same plane as metatarsals II and IV, which is only seen in Patagopteryx, Archaeorhynchus and Hongshanornis among ornithuromorphs. Yet the metatarsus is unlike enantiornithines in having an unreduced metatarsal IV, though this is present in some juveniles such as GMV-2158. It is also unlike most enantiornithines in having metatarsal II's trochlea be wider than III's, though longipterygids, Vorona and Liaoningornis are exceptions. The pubic peduncle is not transversely compressed as occurs in longipterygids though. This may be a non-ornithothoracine avebrevicaudan, or perhaps a juvenile liaoningornithid.
Reference- Sanz, Chiappe, Fernadez-Jalvo, Ortega, Sanchez-Chillon, Poyato-Ariza and Perez-Moreno, 2001. An Early Cretaceous pellet. Nature. 409, 998-999.

Omnivoropterygiformes Czerkas and Ji, 2002
= Sapeornithiformes Zhou and Zhang, 2006
Omnivoropterygidae Czerkas and Ji, 2002
= "Sapeornithidae" Yuan, 2005
= Sapeornithidae Zhou and Zhang, 2006
Comments- Czerkas and Ji (2002) erected Omnivoropterygidae as a monotypic family for Omnivoropteryx, though it has been basically ignored in the literature since. Yuan (2005) named Sapeornithidae in his unpublished thesis for Sapeornis and Didactylornis (with no mention of Omnivoropteryx), and the family was later published by Zhou and Zhang for Sapeornis alone (Didactylornis was unpublished, and Omnivoropteryx again ignored). Yet the ICZN states that Omnivoropterygidae must have priority if Sapeornis belongs to the same family as Omnivoropteryx, even if the latter is found to be a junior synonym of the former.
Both Omnivoropterygiformes and Sapeornithiformes were named as monotypic orders, so they are currently redundant with respect to Omnivoropterygidae.
References- Czerkas and Ji, 2002. A preliminary report on an omnivorous volant bird from Northeast China. Feathered Dinosaurs and the Origin of Flight. The Dinosaur Museum Journal. 1, 127-135.
Yuan, 2005. Restudy on sapeornithids from the Lower Cretaceous of Yixian County, Liaoning. PhD Thesis. China University of Geosciences. 157 pp.
Zhou and Zhang, 2006. Mesozoic birds of China- A synoptic review. Vertebrata PalAsiatica. 44(1), 60-98.

Sapeornis Zhou and Zhang, 2002
= Omnivoropteryx Czerkas and Ji, 2002
= "Didactylornis" Yuan, 2005
= Didactylornis Yuan, 2008
S. chaoyangensis Zhou and Zhang, 2002
= Omnivoropteryx sinousaorum Czerkas and Ji, 2002
= "Didactylornis jii" Yuan, 2005
= Didactylornis jii Yuan, 2008
= Sapeornis angustis Provini, Zhou and Zhang, 2009
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
Holotype- (IVPP V12698) four cervical vertebrae, ten dorsal vertebrae, seven dorsal ribs, gastralia, several caudal vertebrae, pygostyle (~25 mm), scapulae (~75, 75 mm), coracoids (~40 mm), furcula (43.1 mm), humeri (126.5, 129.6 mm), radii (133, 131.9 mm), ulnae (133.1, 135.1 mm), radiale, metacarpal I (14.3 mm), phalanges I-1 (33.6 mm), manual ungual I (~19.1 mm), carpometacarpi (II 57.1 mm, III 54.6 mm), phalanges II-1 (30, 32.2 mm), phalanges II-2 (27.7 mm), manual ungual II (~18 mm), phalanx III-1, phalanx III-2, ilia (~56 mm), pubes (85.4, 87 mm), ischia (42.1 mm), femur (80.4 mm), tibiotarsus (83.6 mm), fibula (~72.4 mm), distal tarsal, tarsometatarsus (44.6 mm), over eight pedal phalanges, pedal ungual, metatarsal V
Referred- ?(CAGS-02-IG-gausa-3/DM 609; holotype of Omnivoropteryx sinousaorum) (subadult) skull, mandible, two cervical vertebrae, ten dorsal vertebrae, dorsal ribs, sacrum, scapulae (one partial), proximal coracoid, humeri (one incomplete; 100 mm), ulnae (one partial; 96.5 mm), radius, phalanx I-1, manual ungual I, metacarpal II (46.5 mm), phalanx II-1, phalanx II-2, manual ungual II, metacarpal III, partial ilium, pubes (51 mm), femora (61 mm), tibiotarsi (one incomplete; 67 mm), fibula, metatarsals I, phalanges I-1, pedal unguals I, metatarsals II (one partial), phalanges II-1, phalanges II-2, pedal unguals II, metatarsals III (one partial; 35 mm), phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, metatarsals IV (one partial), phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV (Czerkas and Ji, 2002)
?(CAGS-03-07-08) incomplete skull (65 mm), partial mandibles, eleven cervical vertebrae, six or seven dorsal vertebrae, twelve pairs of dorsal ribs, gastralia, sacrum, caudal vertebrae, pygostyle (20 mm), scapulae (one partial; ~72 mm), coracoids (one partial; 33 mm), furcula, humeri (130 mm), radii (~124 mm), ulnae (~129 mm), metacarpals I (~12 mm), phalanges I-1 (30 mm), manual unguals I (12 mm straight, 21 mm on curve), carpometacarpi (II 58 mm, III 50 mm), phalanges II-1 (26 mm), phalanges II-2 (24 mm), manual unguals II (12 mm straight, 15 mm on curve), phalanges III-1 (~12 mm), phalanx III-2 (~6 mm), ilia (one partial; 42 mm), pubes (82 mm), partial ischia (23 mm), femora (~78 mm), tibiotarsi (~86 mm), partial fibulae, metatarsals I (11 mm), phalanges I-1 (15 mm), pedal unguals I (12 mm straight, 15 mm on curve), tarsometatarsi (one incomplete; II 37 mm, III 39 mm, IV 38 mm), phalanges II-1 (11 mm), phalanges II-2 (12 mm), pedal unguals II (13 mm straight, 16 mm on curve), phalanges III-1 (12 mm), phalanges III-2 (11 mm), phalanges III-3 (11 mm), pedal ungual III (~12 mm straight), phalanges IV-1 (8 mm), phalanges IV-2 (7 mm), phalanges IV-3 (7 mm), phalanges IV-4 (8 mm), pedal unguals IV (~13 mm straight), metatarsals V (6 mm) (Yuan, 2005)
(CDPC-02-08-001; holotype of Didactylornis jii) skull (72 mm), mandibles (~55 mm), six cervical vertebrae, ten dorsal vertebrae, dorsal ribs, fragmentary gastralia, five sacral vertebrae, less than eight caudal vertebrae, pygostyle, scapulae (one incomplete; 67 mm), coracoids (one incomplete), incomplete furcula, humeri (135 mm), radii (~130 mm), ulnae (138 mm), radiale, ulnare, metacarpal I + phalanx I-1 (50 mm), manual unguals I (19 mm straight), carpometacarpus (II 59 mm, III 56 mm), phalanges II-1 (34 mm), phalanges II-2 (31 mm), manual unguals II (12 mm straight), phalanges III-1, phalanges III-2 (13 mm), partial ilium, pubes (90 mm), ischium (~31 mm), femora (80 mm), tibiotarsi (90 mm), fibula (~78 mm), metatarsals I (14 mm), phalanges I-1 (18 mm), pedal unguals I (one incomplete; 15 mm straight, 18 mm on curve), tarsometatarsi (II 42 mm, III 43 mm, IV 42 mm), phalanges II-1 (13 mm), phalanges II-2 (13 mm), pedal unguals II (14 mm straight, 18 mm on curve), phalanges III-1 (14 mm), phalanges III-2 (11 mm), phalanges III-3 (12 mm), pedal unguals III (13 mm straight, 19 mm on curve), phalanges IV-1 (9 mm), phalanges IV-2 (7 mm), phalanges IV-3 (10 mm), pedal unguals IV (13 mm straight, 16 mm on curve), metatarsal V (Yuan, 2005)
(IVPP V13275) skull (~62 mm), mandible, dentary, atlas, cervical vertebrae, dorsal vertebrae, dorsal ribs, gastralia, sacrum, six or seven caudal vertebrae, pygostyle (~27 mm), scapulae (~71, ~71.5 mm), coracoids (36.7 mm), furcula (~41.5 mm), humeri (one incomplete; 122.6 mm), radii (120, 120.4 mm), ulnae (~123.6, ~124 mm), ulnares, metacarpals I (~11, ~12 mm), phalanges I-1 (28.7, 30 mm), manual unguals I (~18.6 mm), carpometacarpi (II ~52, 51.3 mm, III ~49, 47 mm) phalanges II-1 (one partial; ~29 mm), phalanges II-2 (~26, 25.9 mm), manual unguals II (17.4 mm), phalanx III-1 (10.6 mm), ilia (55.3, 53 mm), pubis (~77.5 mm), ischium (~41.9 mm), femora (74.4, ~73.7 mm), tibiotarsi (80.6, 81.7 mm), fibula (~71, ~68 mm), metatarsal I (10.8 mm), phalanges I-1 (16 mm), pedal unguals I (17.9 mm), tarsometatarsi (~41.5, ~42 mm), pedal ungual II, pedal ungual III, pedal ungual IV, pedal phalanges, metatarsal V (9.6 mm), many gastroliths (2-2.5 mm) (Zhou and Zhang, 2003)
(IVPP V13276) skull (~64 mm), partial surangular, cervical vertebrae, dorsal vertebrae, dorsal ribs, fifteen pairs of gastralia, sacrum, caudal vertebrae, pygostyle (24.3 mm), coracoid (39.5 mm), furcula (42.4 mm), humerus (~123.2 mm), radius (123.3 mm), ulna (124 mm), ulnare, radiale, metacarpal I (12 mm), phalanx I-1 (~27 mm), manual ungual I (18.8 mm), carpometacarpus (II 52.9 mm, III 48.2 mm), phalanx II-1 (30.6 mm), phalanx II-2 (26.6 mm), manual ungual II (~17.7 mm), phalanx III-1 (10 mm), phalanx III-2 (9 mm), ilium (55.9 mm), pubes (80 mm), ischia, femora (72.1 mm), tibiotarsi (one proximal; 85.3 mm), fibula, phalanx I-1 (16.4 mm), pedal ungual I (~17 mm), tarsometatarsi (42 mm), phalanx II-1, phalanx II-2, pedal ungual II, phalanx III-1, phalanx III-2, phalanx III-3, pedal ungual III, pedal ungual IV, pedal claw sheaths, metatarsal V (Zhou and Zhang, 2003)
?(IVPP V13396; holotype of Sapeornis angustis) (subadult) skull (54.5 mm), mandibles, nine cervical vertebrae, two cervical ribs, eleven dorsal vertebrae, twenty-four dorsal ribs, fifteen to sixteen pairs of gastralia, five sacral vertebrae, seven caudal vertebrae, scapulae (52.4, 52.4 mm), coracoids, furcula (42.3 mm), humeri (93.9, 93.1 mm), radii (91.1, 88 mm), ulnae (91.5, 88 mm), radiale, ulnare, metacarpals I (14.2, 11.9 mm), phalanges I-1 (24.1, 24.7 mm), manual unguals I (~10.6, 13.7 mm), metacarpals II (42.8, 41.3 mm), phalanges II-1 (22.3, 23.4 mm), phalanges II-2 (one proximal; 21.7, 21.7 mm), manual unguals II (13.1, 13.7 mm), metacarpals III (36 mm), phalanges III-1 (9.8, 7.5 mm), manual claw sheaths, ilia (30.4 mm), pubes (57.3, 58.5 mm), ischia, femora (one incomplete; 58.2, 58.3 mm), tibiotarsi (68.5, 68.4 mm), fibulae (65.7 mm), distal tarsals III, distal tarsals IV, metatarsal I, phalanges I-1 (12.7, 13.1 mm), pedal unguals I (13.7, 13.7 mm), metatarsals II, phalanges II-1, phalanges II-2, pedal unguals II, metatarsals III (30, 33.1 mm), phalanges III-1, phalanges III-2 (one incomplete), partial phalanges III-3, pedal ungual III, metatarsals IV, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, pedal claw sheaths (Nesbitt et al., 2009)
(IVPP coll.) specimen including posterior cervical vertebrae, dorsal rib, scapulae, coracoids, furcula and humeri (Nesbitt et al., 2009)
(LPM B00166) (one year old subadult) specimen including femur (80 mm) (Erickson et al., 2009)
?(JZPM-LSV-130) skull (60 mm), mandibles (53 mm), ten cervical vertebrae, dorsal vertebra, dorsal ribs, fragmentary gastralia, caudal vertebra, partial coracoids, furcula, incomplete humeri (114 mm), incomplete radii (115 mm), ulnae (one incomplete; 115 mm), radiales, ulnare, metacarpals I (12 mm), phalanges I-1 (~28.5 mm), manual unguals I (16 mm straight, 21 mm on curve), carpometacarpi (one partial; II 53 mm), phalanges II-1 (one partial; 22 mm), phalanges II-2 (one partial; ~14 mm), manual unguals II (13 mm straight, 18 mm on curve), femur (68 mm), tibiotarsi (78 mm), fibula (75 mm), metatarsals I, phalanges I-1 (15 mm), pedal unguals I (14 mm straight, 17 mm on curve), tarsometatarsi (II 38 mm, III 39 mm, IV 38 mm), phalanges II-1 (~8 mm), phalanges II-2 (10 mm), pedal unguals II (13 mm straight), phalanges III-1 (12 mm), phalanges III-2 (11 mm), phalanges III-3 (11 mm), pedal unguals III (13 mm straight), phalanges IV-1 (8 mm), phalanges IV-2 (7 mm), phalanges IV-3 (7 mm), phalanges IV-4 (8 mm), pedal unguals IV (11 mm straight, 15 mm on curve), pedal claw sheaths (Yuan, 2005)
Diagnosis- (after Zhou and Zhang, 2002) large size (also in Yandangornis); forelimb about 1.5 times hindlimb length;
(after Zhou and Zhang, 2003) long hypocleidium on furcula (also in enantiornithines); elongated oval foramen in deltopectoral crest of humerus (also in Confuciusornis); manual digit III consists of two phalanges.
(proposed) dentary toothless (also in Jixiangornis, Zhongjianornis and Confuciusornithidae); sternum unossified (also in Anchiornis and Archaeopteryx); manual phalanx II-2 less than 98% of II-1 (also in Jixiangornis, Yandangornis, Dalianraptor and Changchengornis); metacarpal III straight (also in Scansoriopteryx, Dalianraptor, Zhongornis and some Confuciusornis specimens).
Other diagnoses- Zhou and Zhang (2002) included many symplesiomorphies (deltopectoral crest measures about one third of humeral length; first digit longer than metacarpus; fibula reaches tarsus; fifth metatarsal present) and an avebrevicaudan synapomorphy (pygostyle) in their diagnosis. The tibiofemoral ratio (104-118%) overlaps that of Shenzhouraptor, Jixiangornis and confuciusornithids. Some characters are only present in some specimens (short coracoid; distally pointed deltopectoral crest; tibiotarsus shorter than pubis).
Zhou and Zhang (2003) later added further apomorphies, but the robust furcula is shared with many other basal avialans.
Yuan (2005) included several additional symplesiomorphies were supposed to differentiate it from Didactylornis (phalanx I-1 shorter [i.e. unfused to metacarpal I]; manual digit III unfused to digit II; five phalanges in pedal digit IV). These characters in the Didactylornis holotype may eventually prove to be distinctive for adult Sapeornis.
Comments- The holotype was discovered in 2000, and described in 2002 by Zhou and Zhang. It was originally restored with four phalanges on manual digit III, but was later found to have only two phalanges (Zhou and Zhang, 2002b). Similarly, the hypocleidium was unrecognized in the holotype (Zhou and Zhang, 2003) and is apparently broken in JZPM-LSV-130 as well. Zhou and Zhang (2003) redescribed the holotype and two new specimens (IVPP V13275 and V13276) in detail, while Yuan (2005) described two additional specimens (CAGS-03-07-08 and JZPM-LSV-130) in his unpublished thesis. Parts of the latter specimens are illustrated in his 2008 paper as well. Nesbitt et al. (2009) illustrate parts of two additional specimens, one labeled IVPP V13396 in the figure (8B) and the other (8C) IVPP unnumbered. However, the text states 8B is IVPP V13276 and 8C is V13275. This is obviously untrue, as they are not the specimens described by Zhou and Zhang (2003). The specimen IVPP V12675 is incorrectly stated in the text as being from Zhou and Zhang (2003), but is a paratype of the rodent Advenimus ulungurensis, so must be a mistake. IVPP V13396 was later described as Sapeornis angustis by Provini et al. (2009).
There may be more than one species involved. JZPM-LSV-130 may have short dorsal premaxillary processes, unlike IVPP V13275 and V13276. If the quadratojugal is correctly identified, its lack of a dorsal process is also unlike IVPP V13276. The supposed jugal of JZPM-LSV-130 is too slender, so is more probably a pterygoid. All preserved skulls are distorted to varying degrees, making elements' shapes differ markedly between specimens. The holotype has a somewhat distally expanded, but robust coracoid with a minimum shaft width 51% of its maximum proximodistal length. IVPP V13276 is similar in being robust (58%), but differs in having a lateral process, proximally projecting acromion and distolaterally slanting distal edge. The coracoid of IVPP V13275 is visible in posterodorsal view, so is distorted, but seems roughly similar to both specimens. That of IVPP coll. (Nesbitt et al., 2009 figure 8C) is similar as well. However, the coracoid of CAGS-03-07-08 and the Didactylornis holotype are quite different, being an elongate strut with a very narrow neck (13%) and expanded proximal end (as in other pygostylians). A fragment from JZPM-LSV-130 seems similar. The coracoids of the holotype and CAGS-03-07-08 are the same length relative to their scapulae (~50%), showing the shorter coracoids are not simply due to breakage.
Omnivoropteryx- The holotype of Omnivoropteryx is largely unprepared and only x-rays are available, making most details impossible to discern.
Czerkas and Ji included numerous characters in their diagnosis which are found in Sapeornis as well- short snout; procumbant premaxillary teeth; large external naris; ventrally curved dentary; humerus and ulna longer than femur and tibiotarsus; forelimb (humerus+radius+metacarpus) over 1.5 times length of hindlimb (femur+tibiotarsus+tarsometatarsus); tibiofemoral ratio 1.10 (1.04-1.18 in Sapeornis); pedal phalanx I-1 longer than other phalanges. The supposedly absent manual phalanx III-2 may simply be inconspicuous in the x-rays, as it is a tiny bone in Sapeornis. Indeed, the supposed III-1 in Omnivoropteryx seems to merely be the distal end of metacarpal III, leaving no phalanges from digit III visible. The unfused metatarsus may be due to its ontogenetic state, as the Omnivoropteryx holotype is smaller than specimens referred to Sapeornis chaoyangensis. The authors further state that "significant skeletal differences between the two birds, especially regarding the proportions limbs and pubis" exist, but the slightly shorter ulna (158% of femoral length compared to 165-173% in Sapeornis) may be ontogenetic or individual variation, while the tibiotarsofemoral and metatarsofemoral ratios overlap the variation in Sapeornis. The pubofemoral ratio (84%) is indeed much smaller than in Sapeornis (104-113%), but juvenile enantiornithines also have shorter pubes. While maxillary teeth were reported to be indiscernable, a couple may be visible, comparable to Sapeornis. The first manual digit appears shorter than Sapeornis, but metacarpal I is not apparent in the x-rays, so phalanx I-1 may be placed too proximally. There may be additional differences, but this will not be confirmed until the specimen is properly prepared. The taxon is thus provisionally synonymized with Sapeornis chaoyangensis.
Czerkas and Ji interpreted the cranial similarities between Omnivoropteryx, Caudipteryx and Eoenantiornis as indicating close phylogenetic relationships, but there is little evidence to suggest this. Of the characters listed, the external naris of Caudipteryx is smaller than Omnivoropteryx, Eoenantiornis and almost every other avialan. Procumbant premaxillary teeth and short snouts are present in most basal members of maniraptoran lineages, including Archaeopteryx, basal ornithothoracines, Epidexipteryx, Jinfengopteryx and Incisivosaurus. The decurved dentary is found in many other basal birds too (including Shenzhouraptor, Dalianraptor and Jixiangornis), and Epidexipteryx, as well as derived oviraptorosaurs and therizinosaurs, but not basal varieties (e.g. Falcarius, Incisivosaurus, Protarchaeopteryx). The distribution suggests convergent development. Furthermore, omnivoropterygids possess no oviraptorosaurian characters, and share many synapomorphies with pygostylians. The latter include characters not obviously associated with flight (e.g. partially heterocoelous cervical centra; lateral fossae on posterior dorsal centra; no hyposphene-hypantrum articulations in dorsals; large number of sacral vertebrae; distally tapered scapula; short metacarpal I; short pubic symphysis; large posterodorsal ischial process; obturator process absent; trochanteric crest on femur; fused tibiotarsus). The conclusion is that while omnivoropterygids have superficially caudipterid-like skulls, the similarities are convergent and/or symplesiomorphic, and the family belongs in Avialae as all phylogenetic analyses have concluded.
Nearly all references have ignored Omnivoropteryx, perhaps due to the unusual method of publication and/or personal issues with Czerkas. One of the few exceptions is Dyke and Nudds (2008), who included the taxon without comment in their table of enantiornithines, almost certainly incorrectly.
Didactylornis- Yuan first named and described Didactylornis jii in his PhD thesis, but it was not published until three years later. The thesis contains additional measurements and figures compared to the published paper.
Yuan distinguished Didactylornis from the contemporaneous Sapeornis based on several features. Manual phalanx I-1 was supposed to be longer (85% of metacarpal II compared to 51-59%), but the first phalanx has the odd characteristic of extending proximally to the base of the carpometacarpus, with no separate metacarpal I. Thus it seems plausible that its length is due to fusion with metacarpal I, as in Sapeornis metacarpal I plus phalanx I-1 equal 72-84% of metacarpal II's length. The fusion would still be diagnostic however. Yuan furthermore stated the third manual digit was reduced to the point where it lacks phalanges, but this appears to be problematic as well. In the well preserved left manus, the structure labeled phalanx II-1 seems to be a composite element. There is a slot on its proximolateral portion that defines a narrow phalanx III-1, which may even be defined distally by a suture. Distal to this is another section that also seems separated from II-1 by a suture and ends lateral to digit II in a rounded distal end. Unlike phalanx III-2 in Sapeornis (CAGS-03-07-08, IVPP V13276), it does not taper distally, and extends to almost the end of phalanx II-1. The right manus seems to have a third digit as well, which equally long, though the entire manus and forearm are distorted. The final distinguishing character is the presence of only four phalanges (including the ungual) on digit IV in both pes, which is also known in the Solnhofen Archaeopteryx specimen. Unfortunately, pedal phalanges of digit IV are indistinct or disarticulated in most Sapeornis specimens (holotype, IVPP V13275 and 13276), making the extent of variation uncertain. The only other obvious difference between this specimen and Sapeornis is the strongly flared distal pubis, which forms an arrowhead shape, if not merely due to crushing each pubic boot out laterally. The codings for Sapeornis and Didactylornis are identical in Yuan's matrix (based on Clarke's matrix), except for the last two characters, which are apomorphies of Didactylornis discussed above. The newly described Sapeornis angustis is a subadult specimen which combines characters from Didactylornis (straight ulna; distally blunt manual phalanx III-2 fused to II-2) and Sapeornis (short manual phalanx III-1; five phalanges on pedal digit IV), reducing the likelihood the genera are distinct. It's also notable that the largest and most fully grown Archaeopteryx specimen differs from other specimens in some of the same ways (more manual fusion, reduced number of phalanges on pedal digit IV) that Didactylornis differs from the generally smaller Sapeornis specimens. Didactylornis is probably an ontogenetically older specimen of Sapeornis.
Sapeornis angustis- Provini et al. (2009) described the nearly complete skeleton IVPP V13396 as a new species of Sapeornis, S. angustis. This was based on several characters, but virtually all of them are known to be true in young specimens of other basal birds- small size; fewer sacral vertebrae; narrower furcular rami; shorter hypocleidium; short forelimb (146% compared to 151-156% in specimens described as S. chaoyangensis, 149% in Omnivoropteryx); lower deltopectoral crest; small humeral fenestra; short pubis. The less developed distal corner of the deltopectoral crest is also easily explainable by a young individual being less ossified. Numerous features of the specimen indicate a young age as well- sacral vertebrae not fused; poorly ossified distal ends of long bones; unfused carpometacarpus; unfused tarsometatarsus (while stated to be merely not well fused, there is no fusion apparent and distal tarsals can be seen in both feet though they are not mentioned). While the pubic symphysis is stated to be shorter in the diagnosis, it is stated to be equal in length to S. chaoyangensis in the text and the measurement table confirms this (both have symphyses 33% of pubic length). The shorter ulna (97% of humeral length) is very close to the length in specimens described as S. chaoyangensis (99-105%) and identical to the subadult Omnivoropteryx holotype, so is likely ontogenetic as well. Provini et al. stated the dorsal ribs of angustis were less curved than chaoyangensis, but while this seems true compared to IVPP V13276, it doesn't appear true in V13275. It is thus better explained by individual variation. The one remaining character is the longer metacarpal I (29-33% of metacarpal II length compared to 21-25% in Sapeornis chaoyangensis). It is not only confusing why Provini et al. would ignore ontogeny, but also why they would ignore Omnivoropteryx if they insist on taxonomic separation, as its holotype shares all the supposedly diagnostic characters of S. angustis where they can be observed (small size, short forelimb, low deltopectoral crest with unprojected distal edge, short pubis). It's especially telling that Omnivoropteryx is intermediate in size between angustis and chaoyangensis and also has intermediate deltopectoral crest development and forelimb length, though the pubis is shorter than either.
References- Czerkas and Ji, 2002. A preliminary report on an omnivorous volant bird from Northeast China. Feathered Dinosaurs and the Origin of Flight. The Dinosaur Museum Journal. 1, 127-135.
Zhou and Zhang, 2002a. Largest bird from the Early Cretaceous and its implications for the earliest avian ecological diversification. Naturwissenschaften. 89, 34-38.
Zhou and Zhang, 2002b. A long-tailed, seed-eating bird from the Early Cretaceous of China. Nature. 418, 405-409.
Zhou and Zhang, 2003. Anatomy of the primitive bird Sapeornis chaoyangensis from the Early Cretaceous of Liaoning, China. Canadian Journal of Earth Sciences. 40, 731-747.
Yuan, 2005. Restudy on sapeornithids from the Lower Cretaceous of Yixian County, Liaoning. PhD Thesis. China University of Geosciences. 157 pp.
Dyke and Nudds, 2008. The fossil record and limb disparity of enantiornithines, the dominant flying birds of the Cretaceous. Lethaia. 42(2), 248-254.
Yuan, 2008. A new genus and species of Sapeornithidae from Lower Cretaceous in Western Liaoning, China. Acta Geologica Sinica. 82(1), 48-55.
Nesbitt, Turner, Spaulding, Conrad and Norell, 2009. The theropod furcula. Journal of Morphology. DOI: 10.1002/jmor.10724
Provini, Zhou and Zhang, 2009. A new species of the basal bird Sapeornis from the Early Cretaceous of Liaoning, China. Vertebrata PalAsiatica. 47(3), 194-207.
Erickson, Rauhut, Zhou, Turner, Inouye, Hu and Norell, 2009. Was dinosaurian physiology inherited by birds? Reconciling slow growth in Archaeopteryx. PLoS ONE. 4(10), e7390. doi:10.1371/journal.pone.0007390

Pygostylia Chatterjee, 1997
Definition- (Confuciusornis sanctus + Passer domesticus) (modified from Chiappe, 2001)
Other definitions- (fused distal caudal vertebrae homologous with Vultur gryphus) (Gauthier and de Queiroz, 2001)
= Aerialae Ji and Ji, 2001
= Ornithuromorpha sensu Chiappe, 2001
Definition- (Vorona berivotrensis + Patagopteryx deferrariisi + Passer domesticus) (modified)
Diagnosis- premaxillae fused anteriorly (also in Caenagnathoidea; absent in Pengornis); dorsal centra with enlarged lateral fossae (also in Patagonykus, Beipiaosaurus, Rahonavis, Zhongjianornis and last two dorsals of Sapeornis; absent in juvenile confuciusornithids, Longipteryx, Eocathayornis, Patagopteryx, Apsaravis, Enaliornis and Aves); sternal plates fused (also in Parvicursorinae, some Microraptor specimens, Jixiangornis and Yandangornis); biceps tubercle or scar present on ulna (also in Mononykus and some dromaeosaurids; absent in Protopteryx); posterodorsal ischial process contacts ilium (also in Zhongjianornis; absent in Ornithuromorpha); retinaculi extensor tubercle present on anterodistal tibiotarsus (also in Troodon; absent in Soroavisaurus and Archaeorhynchus); cartilaginous tibial sulcus on posterodistal tibiotarsus.

= Confuciusornithidae sensu Sereno, in press
Definition- (Confuciusornis sanctus <- Passer domesticus)

Confuciusornithiformes Hou, Zhou, Gu and Zhang, 1995
Confuciusornithidae Hou, Zhou, Gu and Zhang, 1995
Definition- (Confuciusornis sanctus + Changchengornis hengdaoziensis) (Chiappe et al., 1999)
Other definitions- (Confuciusornis sanctus <- Passer domesticus) (Sereno, in press)
= Orthornithes Ji and Ji, 2001
Diagnosis- (after Ji et al., 1999) premaxilla toothless (also in Shenzhouraptor, Jixiangornis, Yandangornis, Zhongjianornis, Boluochia+Gobipteryx, Chaoyangiidae, Ornithurae sensu Chiappe); dentary toothless (also in Jixiangornis, Omnivoropterygidae, Zhongjianornis, Gobipteryx, Archaeorhynchus, Apsaravis and Aves); enlarged deltopectoral crest; manual ungual II much smaller than manual ungual I.
(after Chiappe et al., 1999) manual phalanx III-2 >150% of III-1 in length.
(proposed) extremely reduced antorbital fenestra; dentary symphysis fused (polymorphic; also in Shenzhouraptor, Gobipteryx, Apsaravis and Aves); scapula expanded distally; scapulocoracoid fused in adults; coracoid glenoid facet proximal to coracoid tubercle (also in non-ornithurines sensu Gauthier); elongate metatarsal V compared to tarsmetatarsal length; two elongate retrices with reduced barbs (also in Enantiornithes).
Other diagnoses- Ji et al. (1999) included several other characters in their diagnosis. The forked anteromedian dentary margin is plesiomorphically due to a lack of complete fusion. The lack of a promaxillary fenestra and round maxillary fenestra are pygostylian symplesiomorphies. The V-shaped caudal sternal margin is another symplesiomorphy, seen in Shenzhouraptor, Protopteryx and others.
Chiappe et al. (1999) listed an additional supposed synapomorphy. The unfused metacarpal I is a symplesiomorphy however.
Comments- Hou et al. (1999) erected both Confuciusornithidae and Confuciusornithiformes as monotypic taxa for Confuciusornis sanctus. The description of Changchengornis by Ji et al. (1999) first made Confuciusornithidae a useful taxon, though Confuciusornithiformes is still unused except by those authors who assign every Mesozoic bird to an order.
I agree with Sereno (in press) that as more members of the confuciusornithid stem are discovered, it would be ideal to be able to refer them to the family. "Proornis" is a relevent example. Another solution would be to use Confuciusornithiformes (Hou et al., 1995) for the stem. I don't mind either possibility, but would suggest a stem-based definition include Enantiornis leali as an additional external specifier, to satisfy the Sauriurae crowd. As a common stand-in for Pygostylia, Confuciusornis has had some odd relationships in a couple recent analyses (sister to Oviraptorosauria in Maryanska et al., 2002; sister to Microraptor in Mayr et al., 2005). But without additional pygostylians tested in those analyses, it's difficult to justify using those sister taxa as additional specifiers for Confuciusornithidae.
References- Hou, Zhou, Gu and Zhang, 1995. Confuciusornis sanctus, a new Late Jurassic sauriurine bird from China. Chinese Science Bulletin. 40(18), 1545-1551.
Chiappe, Ji, Ji and Norell, 1999. Anatomy and systematics of the Confuciusornithidae (Theropoda: Aves) from the Late Mesozoic of Northeastern China. Bulletin of American Museum of Natural History. 242, 1-89.
Ji, Chiappe and Ji, 1999. A new Late Mesozoic confuciusornithid bird from China. Journal of Vertebrate Paleontology. 19(1), 1-7.
Zinoviev, 2009. An attempt to reconstruct the lifestyle of confuciusornithids (Aves, Confuciusornithiformes). Paleontological Journal. 43(4), 444-452.

"Proornis" Lim, 1993 vide Pak and Kim, 1996
"P. coreae" Lim, 1993 vide Pak and Kim, 1996
Barremian-Albian, Early Cretaceous
Sinuiju series, North Korea
Material- (Kinnissei University Natural Sciences Museum coll.) skull, anterior cervical vertebrae, partial dorsal rib, incomplete humerus, radius, ulna, radiale, metacarpal I, phalanx I-1, manual ungual I, carpometacarpus, phalanx II-1, phalanx II-2, manual ungual II, phalanx III-1, phalanx III-2, phalanx III-3, manual ungual III, feathers
Diagnosis- (proposed) manual phalanx II-2 >115% longer than II-1.
Comments- This specimen was discovered in 1993 and first reported as being Late Jurassic in age, with photographs in the popular press in Korea (October 22, 1993 issue of Nodong Sinmum). It was featured in a 1994 issue of the magazine Korean Pictorial as the "North Korean Archaeopteryx", with a color photo. Molnar (vide Morer-Chauvire, 1994) reported on this in the SAPE newsletter, noting several details including the repository and a few differences from Archaeopteryx (metacarpals shorter compared to radius; digit III phalanges shorter compared to metacarpal III; only three phalanges on manual digit III [which is incorrect]). Similarly, Chiappe (1995) noted that differences in wing proportions cast doubt on its assignment to Archaeopteryx. Pak and Kim (1996) claimed the bird was named "Proornis coreae" by Lim in 1993, by order of Kim Il Sung, although such a publication has not been located to my knowledge. Thus the exact status of the name is uncertain, since the extent of the original description is unknown and no known publication is sufficient as of yet. It remains a nomen nudum on this site until proven otherwise. Pak and Kim also provide a photograph of the specimen, but do not describe it. Lee et al. (2001) credit the name to Paek [sic] and Kim, and distinguish it from Archaeopteryx based on the digits being shorter than the metacarpals (though this seems untrue based on the photo). In 2001, I used the available photo to present a preliminary description of the specimen on the DML, concluding it was a confuciusornithid. Li and Gao (2007) recently commented further on the specimen in an SVP abstract, where they also view it as a confuciusornithid.
Description- The skull is triangular, but further details are difficult to see. It may be preserved in ventral view, showing the quadrates, basicranium, parasphenoid rostrum, and perhaps a broad palatal shelf, but this is uncertain.
Similarily, little can be said of the series of cervical vertebrae extending posteriorly from the skull.
The proximal half of the humerus is missing, though the shaft is straight and seems more slender than Confuciusornis. The ulna has a slightly sigmoid posterior edge and no semilunate ridge on the dorsal condyle unlike ornithothoracines. The radius is straight, ~85% the width of the ulna, and seems to lack a longitudinal groove, unlike some enantiornithines. They are both more slender than Confuciusornis as well. The manus/ulnar ratio (143%) is identical to Confuciusornis. There appears to be a radiale, and Li and Gao indicate the first metacarpal is unfused to the semilunate and metacarpal II. The first metacarpal is fairly elongate (~50% of metacarpal II), which is only found in confuciusornithids (Confuciusornis zhengi 35%, C. sanctus ~43% and Changchengornis 45%) and Jinfengopteryx among paravians. Phalanx I-1 extends past metacarpal II and there is a large ungual on digit I, showing it is less derived than ornithothoracines. Phalanx II-1 is flattened and expanded, as in ornithurines, but unlike the slight condition in Archaeopteryx and other maniraptorans. Phalanx II-2 is slightly longer than II-1 (~125%), which is longer than most ornithurines (C. sanctus' is 106%, C. zhengi's 105% and Changchengornis' 83%). Manual ungual II is much smaller than the other manual unguals, a condition only known in confuciusornithids and Dalianraptor. Metacarpal III is slightly short than metacarpal II. There are four unreduced phalanges in digit III unlike ornithothoracines and omnivoropterygids, of which III-3 is elongate (~118% longer than III-1 and III-2 combined; compared to 109% in C. sanctus, 126% in C. zhengi and ~130% in Changchengornis). Phalanx III-2 is about 160% longer than III-1, which is otherwise only known in confuciusornithids, Dalianraptor, Sinornithoides and Dilong. The ungual is intermediate in size between those of digits I and III.
Feather imprints are said to be present, although they cannot be discerned in available photos.
Relationships- The characters above suggest that "Proornis" be referred to the Confuciusornithidae, based on the long metacarpal I, reduced manual ungual II and phalanx III-2 much longer than III-1. The only certain difference from Confuciusornis and Changchengornis is the ratio between phalanges II-1 and II-2, though future studies may show more characters which cannot be ascertained from the single available photo.
References- Anonymous, 1993. Nodong Sinmum. October 22, 1993.
Lim, 1993.
Anonymous?, 1994. Korean Pictorial. Volume 2.
Morer-Chauvire, 1994. Society of Avian Paleontology and Evolution Information Letter. Number 8.
Chiappe, 1995. The first 85 million years of avian evolution. Nature. 378, 349-355.
Pak and Kim, 1996. Section 5. Mesozoic Era. in Paek, Kang and Jon (eds.). Geology of Korea, Foreign Languages Books Publishing House, Pyongyang. 155-188.
Lee, Yu and Wood, 2001. A review of vertebrate faunas from the Gyeongsang Supergroup (Cretaceous) in South Korea. Palaeogeography, Palaeoclimatology, Palaeoecology. 165(3), 357-373.
Mortimer, DML 2001. http://dml.cmnh.org/2001May/msg00859.html
Li and Gao, 2007. Lower Cretaceous vertebrate fauna from the Sinuiju basin, North Korea as evidence of geographic extension of the Jehol Biota into the Korean Peninsula. Journal of Vertebrate Paleontology. 27(3), 106A.

Changchengornis Ji, Chiappe and Ji, 1999
C. hengdaoziensis Ji, Chiappe and Ji, 1999
Late Barremian-Early Aptian, Early Cretaceous
Jianshangou Beds of Yixian Formation, Liaoning, China
Holotype- (GMV 2129a/b) (adult male) incomplete skull, incomplete mandibles, four cervical vertebrae, over seven dorsal vertebrae, partial dorsal ribs, gastralia, sacrum, six caudal vertebrae, pygostyle, scapulocoracoids, furcula, incomplete sternum, partial humeri (33.53 mm), partial radii (31.07, 30.35 mm), partial ulnae (31.97 mm), metacarpal I (7.76 mm), phalanges I-1, manual ungual I, metacarpals II (17.07 mm), phalanges II-1 (10.67, 10.91 mm), phalanges II-2 (10.71, 10.89 mm), manual ungual II, partial metacarpals III, phalanges III-1, phalanges III-2, phalanges III-3, manual ungual III, manual claw sheaths, partial ilia, pubes, femora (33.46, 33.02 mm), tibiotarsi (36.59, 36.86 mm), fibulae (20.93, ~19.9 mm), metatarsals I (5.21, 5.13 mm), phalanges I-1, pedal unguals I, tarsometatarsi (20.64, 20.34 mm), phalanges II-1, phalanges II-2, pedal unguals II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, metatarsal V, pedal claw sheaths, body feathers, remiges, retrices
Diagnosis- (after Ji et al., 1999) decurved premaxilla; surangular rises sharply at posterior edge of external mandibular fenestra; metacarpal I >40% of metacarpal II.
(after Chiappe et al., 1999) rostrum <40% of cranial length; tubercle on center of posterior furcula (also in Jixiangornis); furcula grooved anteriorly and posteriorly; manual phalanges II-1 and II-2 subequal in length (also in Jixiangornis, Dalianraptor, Yandangornis and Omnivoropterygidae); metatarsals III and IV fuse distally (also in Yandangornis).
(proposed) humerus subequal to femur in length; brevis fossa present(?).
Other diagnoses- Ji et al. (1999) also used three other characters in their diagnosis. The mandible being much shorter than the skull cannot be confirmed because the anterior dentary does not connect to the posterior mandible in the holotype. The absent proximal humeral foramen is plesiomorphic. The elongated hallux compared to digit II is within the range of variation of Confuciusornis (e.g. IVPP V11308). Chiappe et al. (1999) proposed the narrow posteromedian sternal process as an apomorphy, but this is also within the range of Confuciusornis (e.g. IVPP V11521). Finally, they also included the plesiomorphically non-excavated posterior metatarsus in their diagnosis.
References- Ji, Chiappe and Ji, 1999. A new Late Mesozoic confuciusornithid bird from China. Journal of Vertebrate Paleontology. 19(1), 1-7.
Chiappe, Ji, Ji and Norell, 1999. Anatomy and systematics of the Confuciusornithidae (Theropoda: Aves) from the Late Mesozoic of Northeastern China. Bulletin of American Museum of Natural History. 242, 1-89.

Zhongornis Gao, Chiappe, Meng, O'Conner, Wang, Cheng and Liu, 2008
Z. haoae Gao, Chiappe, Meng, O'Conner, Wang, Cheng and Liu, 2008
Early Aptian, Early Cretaceous
Dawangzhangzi Beds of Yixian Formation, Liaoning, China
Holotype- (D2455/6) (juvenile male) skull, mandibles, hyoid, nine cervical vertebrae, thirteen dorsal vertebrae, dorsal ribs, gastralia, first sacral vertebra, second sacral vertebra, third sacral vertebrae, anterior fourth sacral vertebra, thirteen caudal vertebrae, chevrons, scapulae (~13.1 mm), incomplete coracoids (~6.5 mm), incomplete furcula, humeri (15.9 mm), radii (13.9 mm), ulnae (14.5 mm), semilunate carpal, metacarpal I (2.8 mm), phalanges I-1 (one fragmentary; 8.1 mm), manual ungual I (4.7 mm), metacarpal II (8.6 mm), phalanges II-1 (one partial; 5.5 mm), phalanx II-2 (7.4 mm), manual ungual II (3.2 mm), metacarpal III (7.7 mm), phalanges III-2 (one partial; ~5.2 mm), phalanx III-3 (5.5 mm), manual ungual III (2.9 mm), partial ilia, ischia, femora (15.3 mm), tibiae (20.5 mm), fibula, astragalus, metatarsals I (2.2 mm), phalanges I-1 (1.9 mm), pedal unguals I (1.9 mm), metatarsals II (8.4 mm), phalanges II-1 (2.4 mm), phalanges II-2 (3.4 mm), pedal unguals II (2.7 mm), metatarsals III (9.9 mm), phalanges III-1 (3.2 mm), phalanges III-2 (2.6 mm), phalanges III-3 (3.1 mm), pedal unguals III (2.4 mm), metatarsals IV (9.2 mm), phalanges IV-1 (1.7 mm), phalanges IV-2 (1.7 mm), phalanges IV-3 (1.4 mm), phalanges IV-4 (2.3 mm), pedal unguals IV (2.1 mm), pedal claw sheaths, remiges, retrices
Diagnosis- (after Gao et al., 2008) ancestral manual phalanx III-1 absent or reduced to less than a fifth of the length of III-2.
Other diagnoses- Gao et al. (2008) include several characters in their diagnosis of Zhongornis, whose unique combination was supposed to diagnose it. Of these, the the strut-like coracoid is a pygostylian symplesiomorphy, and the toothless premaxilla and dentary are confuciusornithid symplesiomorphies. The imperforate deltopectoral crest and relative sizes of the manual unguals are plesiomorphic for theropods, while the 13-14 differentiated caudal vertebrae are a juvenile characteristic (as may be the former two).
Comments- Gao et al. (2008) coded Zhongornis as if it were adult, because they viewed the presence of long remiges and retrices as indications it was close to fledging so that "that developmentally, its skeleton was not very far from maturation." However, juvenile enantiornithines also show well developed remiges, yet lack numerous fusion and morphological characters compared to adults. The resulting analysis found Zhongornis to be sister to Pygostylia. Four characters placed Zhongornis outside Pygostylia. Of these, the unfused distal caudal vertebrae are found in juvenile enantiornithines such as Dalingheornis and IVPP V14238. The presence of more than eight free caudal vertebrae is basically a restatement of the same character. The moderate development of the posterior trochanter might be expected in a juvenile, but juvenile enantiornithines do have large trochanters like adults. Finally, the unfused tibiotarsus is seen in juvenile confuciusornithids and enantiornithines. O'Conner et al. (2009) include Zhongornis in a larger phylogenetic analysis, which they state finds Zhongornis as the sister group of Pygostylia. Yet it's placed sister to Longirostravis in their figure, while DNHM D2567/8 (otherwise unmentioned) is sister to Pygostylia. This is likely a typo, with Zhongornis and a mistyped DNHM 2522 (described as a longipterygid) switched. This is supported by the same four characters as Gao et al. (2008), with the addition of two. The lack of lateral fossae on the dorsal centra is explainable by the increased pneumaticity with age, as shown by the subadult Confuciusornis zhengi holotype which has only slight depressions. Similarly, the relatively robust radius of Zhongornis (~78% of ulnar width) is comparable to C. zhengi (73%) and matched by some juvenile enantiornithines (e.g. GMV-2159's is 82%). The conclusion is that the placement of Zhongornis outside Pygostylia is due entirely to juvenile characters, with only the reduced posterior trochanter not found in other juvenile birds so far.
If Zhongornis is a juvenile pygostylian, it is likely to be a confuciusornithid (Mortimer, DML 2008). There are four codings in Gao et al.'s matrix which would exclude Zhongornis from Confuciusornithidae. The deltopectoral crest is lower than in adult confuciusornithids, but this is also true of Confuciusornis zhengi . Juvenile enantiornithines also have lower deltopectoral crests than adults. It should also be noted that the crest in Zhongornis is higher and more quadrangular than most Mesozoic pygostylians, which is a character shared with confuciusornithids. Manual ungual II is not smaller than III, which is indeed unlike confuciusornithids and not known to vary with age. Confuciusornithids have a reduced manual phalanx III-1, while Zhongornis was described as having only two long non-ungual phalanges in digit III. Yet the base of digit III is beneath phalanx II-1, so may incorporate a hidden and reduced proximal phalanx as well. Thus the evidence for excluding Zhongornis from Confuciusornithidae due to this character is at worst equivocal, for even if there are only two non-ungual phalanges in digit III, the missing phalanx could be III-1, which would therefore be reduced as in confuciusornithids. Metatarsal I is coded as being straight in Zhongornis, but J-shaped and twisted in confuciusornithids. Yet the photo (figire 4B) suggests it is curved the same amount as in Confuciusornis, while twisting doesn't seem possible to discern in such a poorly preserved element. Besides the enlarged deltopectoral crest, the toothless premaxilla and dentary are confuciusornithid synapomorphies. Within Confuciusornithidae, Zhongornis may be referrable to Confuciusornis based on the long humerus (which would become even longer with age), long manual phalanx II-2 compared to II-1 and reduced trochlea on metatarsal IV, but this is hard to determine from such a young specimen where adult morphologies may not be developed yet. For instance, the short snout and absence of a humeral foramen are similar to Changchengornis, but these would also be expected in any juvenile. Manual phalanx II-2 is not bowed as it is in Confuciusornis, but this may be ontogenetic. Confuciusornis is the most common theropod in the Yixian formation, so finding a juvenile example is not unexpected. It is retained as a separate taxon here mainly because ontogeny makes definite referral to Confuciusornis uncertain, and Dawangzhangzi Confuciusornis adults have been reported but not described, so may belong to a new species.
References- Gao, Chiappe, Meng, O'Conner, Wang, Cheng and Liu, 2008. A new basal lineage of Early Cretaceous birds from China and its implications on the evolution of the avian tail. Palaeontology. 51(4), 775-791.
Mortimer, DML 2008. http://dml.cmnh.org/2008Jul/msg00256.html
O'Conner, Wang, Chiappe, Gao, Meng, Cheng and Liu, 2009. Phylogenetic support for a specialized clade of Cretaceous enantiornithine birds with information from a new species. Journal of Vertebrate Paleontology. 29(1), 188-204.

Confuciusornis Hou, Zhou, Gu and Zhang, 1995
= Jinzhouornis Hou, Zhou, Zhang and Gu, 2002
= Eoconfuciusornis Zhang, Zhou and Benton, 2008
Diagnosis- (after Hou et al., 1995) maxilla toothless (unknown in Changchengornis); large foramen in proximal humerus of adults (reversed in C. feducciai).
(after Zhou, 1999) dentary strongly forked posteriorly (unknown in Changchengornis); elongate external mandibular fenestra (unknown in Changchengornis); furcular arm width >20% of arm length (unknown in C. dui).
(after Chiappe et al., 1999) dorsal premaxillary edge straight; manual phalanx II-2 bowed.
(proposed) splenial extends to anterior tip of dentary (unknown in C. dui); trochlea of metatarsal IV much smaller than those of metatarsals II and III.
Other diagnoses- Hou et al. (1995; repeated in Hou, 1997) also included several other characters in their diagnosis. Premaxillary and dentary teeth are now known to be absent in Changchengornis as well, along with the correlated grooves and pits in its beak. Two other derived characters are also now known in Changchengornis- reduced antorbital fenestra; proximal humerus expanded. Most characters used are symplesiomorphies- large orbit; manual ungual I long and robust; manual phalanges slender and unreduced; ischium with proximodorsal process; pedal unguals large and curved; metatarsal V present. Confuciusornis' size is not diagnostic, as C. dui is small while the other three valid species are about equal in size. The distal carpal is not unfused to the metacarpals, contra Hou et al.. The robust ischium with "slightly expanded distal end" is a misinterpretation due to the ischium of the paratype being incomplete distally.
Zhou (1999) includes numerous additional characters in his diagnosis, most of them symplesiomorphies of Pygostylia- postorbital robust, Y-shaped and contacts jugal and squamosal; dorsal process of maxilla and nasal separating naris and antorbital fenestra; quadratojugal with slender dorsal process; small, rounded posterior surangular foramen; deep lateral fossae in dorsal centra; gastralia present; seven to nine sacral vertebrae; pygostyle composed of eight to nine vertebrae; coracoid short; sternal keel not pronounced; furcula lacking hypocleidium; humerus slightly longer than ulna; semilunate carpal fused to metacarpal II; metscarpal III subequal in length to II; metacarpal III reduced in width, especially proximally; phalangeal formula of manus 2-3-4; manual ungual III large; manual digits II and III subequal in length; fibula not reaching distal end of tibiotarsus. Three are derived characters now known to be shared with Changchengornis and other confucisornithids- fused scapulocoracoid; manual ungual II reduced; manual phalanx III-1 short. The Y-shaped quadratojugal seems to vary between specimens. Finally, two characters are too vague to evaluate- quadrate high without orbital process developed; ulnare slender.
Chiappe et al. (1999) include a "straight culmen and mandible" in their diagnosis, though technically the culmen (upper beak edge) is concave in the rare case the keratinous beak is preserved (e.g. C. dui holotype). Still, the straight dorsal premaxillary edge is unique. The straight mandible is plesiomorphic, however. The notched anteromedian margin of the premaxillae is seen in more basal taxa as well, but is less obvious there due to a lack of fused premaxillae, so is not a diagnostic character. The retinaculi extensoris tubercle on the anterodistal tibiotarsus is a pygostylian synplesiomorphy. The hallux length is variable in Confuciusornis and can be as long as in Changchengornis (e.g. IVPP V11308).
Zhou and Hou (2002) largely reuse Zhou's (1999) diagnosis, but further specify the sacrum has seven vertebrae (as in other basal avebrevicaudans), the fibula is ~75% of tibiotarsal length (though it is comparable in length in IVPP V11552 and Changchengornis and overlaps other avialans' lengths), and metatarsal V is about a third as long as the tarsometatarsus (shared with Changchengornis).
References- Hou, Zhou, Gu and Zhang, 1995. Confuciusornis sanctus, a new Late Jurassic sauriurine bird from China. Chinese Science Bulletin. 40(18), 1545-1551.
Hou, 1997. Mesozoic birds of China. Taiwan Provincial Feng Huang Ku Bird Park. Taiwan: Nan Tou, 228 pp.
Chiappe, Ji, Ji and Norell, 1999. Anatomy and systematics of the Confuciusornithidae (Theropoda: Aves) from the Late Mesozoic of Northeastern China. Bulletin of American Museum of Natural History. 242, 1-89.
Zhou, 1999. Early evolution of birds and avian flight-evidence from Mesozoic fossils and modern birds. PhD Dissertation, Department of Systematics and Ecology, University of Kansas. 216 pp.
Hou, Zhou, Zhang and Gu, 2002. Mesozoic birds from western Liaoning in China. Liaoning, China: Liaoning Science and Technology Publishing. ISBN 7-5381-3392-5. 120 pp.
Zhou and Hou, 2002. The Discovery and Study of Mesozoic Birds in China. in Chiappe and Witmer, (eds.). Mesozoic Birds- Above the Heads of Dinosaurs. University of California Press, Berkeley, Los Angeles, London. 160-183.
Zhang, Zhou and Benton, 2008. A primitive confuciusornithid bird from China and its implications for early avian flight. Science in China Series D: Earth Sciences. 51(5), 625-639.
C? chuonzhous Hou, 1997
Late Barremian-Early Aptian, Early Cretaceous
Jianshangou Beds of Yixian Formation, Liaoning, China
Holotype- (IVPP V10919) distal tibiotarsus, fibular fragment(?), metatarsal I, phalanx I-1, incomplete pedal ungual I, tarsometatarsus (distal metatarsal II missing; 33 mm), phalanx II-1, distal phalanx II-2, pedal ungual II, phalanx III-1, phalanx III-3, pedal ungual III, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, pedal claw sheaths, body feathers
Diagnosis- indeterminate within Confuciusornis.
Other diagnoses- Hou (1997) listed many problematic characters in his diagnosis. It is not larger than C. sanctus specimens, though it is larger than most. Contra Hou, the tibiotarsus is within the range of robusticity of C. sanctus specimens. Hou cites the tibiotarsal width as 4 mm and the metatarsal length of 33 mm (ratio of 12.1%), compared to the C. sanctus paratype's 2.5 mm and 22 mm respectively (ratio of 11.4%), but C. sanctus specimen GMV-2133 has a ratio of 18.2%. The tibiotarsus is said to be anteroposteriorly thick, but measurements are not cited, and this would be difficult to determine in a specimen which is crushed in anterior view. Contra Hou, the tibiotarsus is clearly expanded distally, as in C. sanctus. The supposedly unfused proximal tarsals (also noted by Zhou, 1995) were found to be only equivocally present by Chiappe et al. (1999), and as noted by them, could be ontogenetic in any case. Based on the photo, the tibiotarsus is much too poorly preserved to determine much structure. Hou lists pedal ungual I's small size and large degree of curvature (a typo for a small degree of curvature, as seen by the description and illustration) as being diagnostic, but the description also mentions digit I having three phalanges. Chiappe et al. believed Hou mistook metatarsal I for another phalanx, but he actually mistook the broken proximal portion of pedal ungual I as another phalanx. This is apparent from photos, his figure and the description, which states the supposed phalanx I-2 is extremely short. It would also explain the ungual's small size and lack of curvature, as only the distal end was interpreted as the ungual by Hou. Finally, Hou lists "metatarsal V is present and is isolated, except for its articulated proximal end", but it is present in C. sanctus as well. The discussion indicates it is metatarsal V's robusticity and lack of fusion with the tarsometatarsus that Hou belives is unique. Examination of photos leads me to believe that what's identified as metatarsal V is actually a broken proximal end of metatarsal II. This would explain why the metatarsus is so narrow, and why metatarsals I and V are on the same side. The discussion adds a couple additional characters supposedly distinguishing C. chuonzhous from C. sanctus. The distal tibiotarsal condyles are said to be inconspicuous and not anteriorly projected, but as noted above, the tibiotarsus is far too poorly preserved to judge this. It is said to have probably possessed at least two distal tarsals, while C. sanctus is described as having only one. Yet C. sanctus has its distal tarsals fused to the metatarsus (the single tarsal identified in a paratype by Hou is probably part of the astragalar condyles), while Hou earlier says distortion makes it hard to assess the presence of distal tarsals in C. chuonzhous, but that he assumes they were unfused based on the specimen's primitive morphology, and were perhaps not preserved! The photo shows no evidence for free tarsals, the structure representing such in the illustration being the proximal end of metatarsal III.
Comments- This specimen was initially listed as a paratype of C. sanctus by Hou et al. (1995a), though it was not illustrated and was mistyped as IVPP V10915 in the measurements paragraph of their later paper (1995b). Hou et al. (1995b) noted the fibula extended to near the distal end of the tibiotarsus, ending in an expansion. This may merely be part of the tibiotarsus, however, and was not mentioned or illustrated by Hou (1997). Hou (1997) erected the species C. chuonzhous for it (erroneously called Confuciusornis meidus in the English summary), based on a number of problematic characters (see above). Chiappe agreed Hou's characters were inadequate and synonymized C. chuonzhous with C. sanctus. Yet the specimen is too fragmentary to determine if it has pedal characters of Confuciusornis as opposed to Changchengornis (distally unfused metatarsals III and IV; metatarsal IV trochlea reduced in size), and Confuciusornis species cannot be distinguished by tibiotarsal or pedal characters yet. The large size and horizon do suggest either C. sanctus or C. feducciai, but it must remain indeterminate within Confuciusornis.
References- Hou, Zhou, Gu and Zhang, 1995a. Confuciusornis sanctus, a new Late Jurassic sauriurine bird from China. Chinese Science Bulletin. 40(18), 1545-1551.
Hou, Zhou, Martin and Feduccia, 1995b. A beaked bird from the Jurassic of China. Nature. 377, 616-618.
Zhou, 1995. New understanding of the evolution of the limb and girdle elements in early birds - Evidences from Chinese fossils. In Sun and Wang (eds). Sixth Symposium on Mesozoic Terrestrial Ecosystems and Biota, short papers. Beijing: China Ocean Press. 209-214.
Hou, 1997. Mesozoic birds of China. Taiwan Provincial Feng Huang Ku Bird Park. Taiwan: Nan Tou, 228 pp.
Chiappe, Ji, Ji and Norell, 1999. Anatomy and systematics of the Confuciusornithidae (Theropoda: Aves) from the Late Mesozoic of Northeastern China. Bulletin of American Museum of Natural History. 242, 1-89.
C. dui Hou, Martin, Zhou, Feduccia and Zhang, 1999
Late Barremian-Early Aptian, Early Cretaceous
Jianshangou Beds of Yixian Formation, Liaoning, China
Holotype- (IVPP V11553) (male adult) skull, horny beak, mandible (40 mm), sclerotic ring, hyoid, cervical vertebrae, dorsal vertebrae, dorsal ribs, gastralia, sacrum, caudal vertebrae, pygostyle (23 mm), proximal scapula, sternum, humeri (42 mm), radii, ulnae (39 mm), metacarpal I, phalanx I-1, manual ungual I, carpometacarpi (19 mm), phalanx II-1, phalanx II-2, manual ungual II, phalanx III-1, phalanges III-2, phalanges III-3, manual unguals III, ilium, femora (35 mm), tibiotarsi (41 mm), metatarsal I, phalanx I-1, pedal ungual I, tarsometatarsi (19.5 mm), phalanges II-1, phalanx II-2, pedal ungual I, phalanges III-1, phalanges III-2, phalanges III-3, pedal ungual III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal ungual IV, body feathers, remiges, retrices
Paratype- (IVPP V11521) vertebrae, ribs, caudal vertebrae, pygostyle, sternum, eight sternal ribs, pelvis, femora
Diagnosis- (after Hou et al., 1999) small size (femur <40 mm in adults) (also in Changchengornis); manual unguals I and III subequal in size.
(proposed) narrow, tapered and vertical ascending process of maxilla without maxillary fenestra; maxilla takes up most of ventral orbital margin; low rounded dorsal jugal process(?); jugal forms ventral margin of laterotemporal fenestra(?); posterodorsal dentary process extends posteriorly over most of mandibular fenestra; posterodorsal dentary process taller than posteroventral process; sternal lateral processes not bifurcate; sternal ribs attach to lateral processes; sternal ribs grow posteriorly shorter, so that last is less than a third as long as the first; last two sternal ribs markedly expanded distally; metacarpal I tapers proximally; tibiotarsofemoral ratio 84% the size of C. sanctus specimens of similar length.
Other diagnoses- The lack of a ventral expansion on the anterior dentary was also cited by Hou et al. (1999) in their diagnosis, but this is a symplesiomorphy compared to C. sanctus and C. feducciai. Contra Hou et al., the premaxilla does not appear to be more pointed anteriorly than C. sanctus. Similarly, the sternum elongation (~74%) falls within the range of variation in C. sanctus (e.g. ~75% in GMV-2131). Some C. sanctus are known to have an anterior notch in their sterna (e.g. IVPP V10928, V13313) as does C. feducciai. Short posterolateral sternal processes are also present in C. sanctus and C. feducciai, so this is not diagnostic of the species either. Finally, the tarsometatarsus is not shorter than in C. sanctus, as the tarsometatarsofemoral ratio is 56%, while C. sanctus' varies from 53-61%.
Chiappe et al. (2008) notes that C. dui is an outlier on plots of limb bone lengths compared to 108 specimens of C. sanctus. This is most obvious in the tibiotarsofemoral plots, where a similarly sized C. sanctus would have a tibiotarsus 48.7 mm long instead of C. dui's 41 mm.
References- Hou, Martin, Zhou, Feduccia and Zhang, 1999. A diapsid skull in a new species of the primitive bird Confuciusornis. Nature. 399, 679-682.
Chiappe, Marugan-Lobon, Ji and Zhou, 2008. Life history of a basal bird: morphometrics of the Early Cretaceous Confuciusornis. Biology Letters. 4(6), 719-723.
C. feducciai Zhang, Gao, Meng, Liu, Hou and Zheng, 2009
Late Barremian-Early Aptian, Early Cretaceous
Jianshangou Beds of Yixian Formation, Liaoning, China
Holotype- (D2454) (adult male) skull, mandibles, atlas, axis, six cervical vertebrae, eleven dorsal vertebrae, eight pairs of dorsal ribs, six uncinate processes, gastralia, synsacrum, five caudal vertebrae, pygostyle (~27 mm), scapula, coracoids, furcula, sternum, four sternal ribs, humeri (78.09 mm), radii, ulnae (69.96 mm), ulnare, metacarpal I, phalanges I-1, manual unguals I, carpometacarpi (32 mm), phalanges II-1, phalanges II-2, manual unguals II, phalanx III-1, phalanx III-2, phalanx III-3, manual ungual III, ilia, pubes, ischia, femora (58.49 mm), tibiotarsi (68.87 mm), fibula, metatarsals I, phalanges I-1, pedal unguals I, tarsometatarsi (33.5 mm), phalanx II-1, phalanx II-2, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal phalanges, pedal unguals, metatarsal V, body feathers, retrices
Diagnosis- (after Zhang et al., 2009) elongate forelimb (humerus+ulna / femur+tibia >110%); foramen absent in deltopectoral crest of humerus (also in Changchengornis); manual phalanx I-1 reduced to be subequal in width to III-3; ischium >50% of pubic length.
(proposed) anterior dentary expanded ventrally (also in C. sanctus); anterolateral sternal processes present; posterolateral sternal processes elongate and directed anterolaterally.
Other diagnoses- Zhang et al. (2009) also included the V-shaped furcula in their diagnosis, but this is seen in some C. sanctus specimens as well (e.g. GMV-2132). They also used the character "sternum broader than long", but is it actually comparable to C. sanctus when the lateral processes are ignored. The deltopectoral crest has the same rectangular shape in Changchengornis and some C. sanctus as well (e.g. Jinzhouornis yixianensis holotype). Large size is not a diagnostic character of the species, as there are larger C. sanctus individuals known (e.g. BSP 1999 I 15). Although Zhang et al. state manual ungual I is "nearly as large" as manual ungual III, unlike C. sanctus, III is 77% as large as I. This is comparable to the ratio of 73% found in C. sanctus and quite unlike the 104% ratio in C. dui.
Comments- The holotype of C. feducciai was used in Chiappe et al.'s (2008) morphometric study as an example of C. sanctus, though it was an outlier in the humerofemoral and ulnofemoral plots in their figure 2. Is it possible that C. feducciai is merely an exceptionally large and ossified individual of C. sanctus? The data seem to argue against this. The sternal characters could easily be due to extra ossification with growth. Yet Confuciusornis seems to gain its humeral foramen with adulthood, and reducing the robusticity of manual digit I with age seems counterintuitive. Furthermore, the forelimb is longer than even comparably sized C. sanctus (e.g. BSP 1999 I 15, GMV-59-1, 2132, IVPP V11370), showing it's not merely the continuation of an allometric trend. The ischiopubic ratio is unknown to vary with age in theropods. The elongate sternal processes, gracile digit I and elongate ischium are actually more similar to ornithothoracines than confuciusornithids, but there are at least ten confuciusornithid characters which argue for its placement in the family.
C. feducciai may be more closely related to C. sanctus than to C. dui based on the ventrally expanded anterior dentary, though the lack of a deltopectoral foramen argues it is outside the sanctus + dui clade.
References- Chiappe, Marugan-Lobon, Ji and Zhou, 2008. Life history of a basal bird: morphometrics of the Early Cretaceous Confuciusornis. Biology Letters. 4(6), 719-723.
Zhang, Gao, Meng, Liu, Hou and Zheng, 2009. Diversification in an Early Cretaceous avian genus: evidence from a new species of Confuciusornis from China. Journal of Ornithology. DOI 10.1007/s10336-009-0399-x
C. zhengi (Zhang, Zhou and Benton, 2008) new comb.
= Eoconfuciusornis zhengi Zhang, Zhou and Benton, 2008
Late Hauterivian, Early Cretaceous
Sichakou Sedimentary Member of the Huajiying Formation, Hebei, China
Holotype- (IVPP V11977; holotype of Eoconfuciusornis zhengi) (subadult male) skull (42 mm), mandibles (35 mm), keratinous beak, hyoids, atlas, axis, cervical vertebrae 3-7, cervical ribs, twelve to fourteen dorsal vertebrae, dorsal ribs, gastralia, first sacral vertebra, second sacral vertebra, fused third to fifth sacral vertebrae, sixth sacral vertebra, seventh sacral vertebra, eight caudal vertebrae, pygostyle (24 mm), scapulae (27 mm), coracoid, furcula, sternum, humeri (one incomplete; 40 mm), radii (one partial), ulnae (one partial; 36 mm), radiale, ulnare, semilunate carpal, metacarpal I (6 mm), phalanx I-1 (16 mm), metacarpal II (19 mm), phalanges II-1 (one proximal; 15 mm), phalanx II-2 (16 mm), manual ungual II (5 mm), metacarpals III (one distal; 13 mm), phalanges III-1 (4, 4 mm), phalanges III-2 (one proximal; 10 mm), phalanx III-3 (11 mm), manual ungual III (7 mm), incomplete ilia, distal pubes, ischium, femora (36 mm), tibiae (43 mm), fibulae, astragali, metatarsals I, phalanges I-1, pedal unguals I, tarsometatarsi (23 mm), phalanges II-1, phalanges II-2, pedal unguals II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, body feathers, remiges, retrices
Diagnosis- (after Zhang et al., 2008) dorsal vertebral centra lacking deep lateral fossae (ontogenetic?; unknown in C. feducciai); acromion process short (ontogenetic?); coracoid proximodistally short; extensor canal of astragalus bridged over (unknown in C. feducciai).
(proposed) enlarged surangular foramen (also in C. sanctus; unknown in C. feducciai); procoelous caudal centra (also in Zhongjianornis); semilunate dorsal condyle of ulna (also in Anchiornis and Zhongjianornis).
Other diagnoses- Zhang et al. (2008) included additional humeral characters in their diagnosis, most of which are viewed below as ontogenetic (low deltopectoral crest on humerus; the redundant proximal end of humerus expanded less than twice the width of distal end; humerus lacks deltopectoral foramen). They also used the elongate tarsometatarsus (53% of tibial length) as a distinguishing character, but the unfused astragalus would subtract another percent or two (it's 1.7 mm deep), and juveniles have longer lower limb elements. In any case, it is not that different from the 47-49% found in Confuciusornis sanctus, well within the range of individual variation.
Comments- Jin et al. (2008) note the bird-bearing beds at Sichakou are the Huajiying Formation, which is above the Dabeigou Formation (contra Zhang et al., 2008).
A large number of characters suggest the holotype is a subadult. These include a small size, course ends of long bones, poorly fused premaxillae, unfused dentaries, unfused cervical ribs, unfused anterior and posterior sacral vertebrae, apparently unossified uncinate processes and sternal ribs, largely unossified sternum, unfused carpometacarpus, tarsus not fused to tibia, and poorly fused metatarsus, in addition to the characters mentioned below. Zhang et al. argue zhengi is nearly an adult based on its supposedly medium size and elongate retrices. Yet the humerus is 40 mm long, which is shorter than any of the 106 specimens examined by Chiappe et al. (2008), even if Zhang et al. do cite one specimen which is smaller (IVPP V10928). It's also quite possible C. zhengi was a bit larger as an adult than C. sanctus. Similarly, juvenile enantiornithines like GMV-2159, Jibeinia and Protopteryx have elongate retrices.
A stem-confuciusornithid?- Zhang et al. (2008) described Eoconfuciusornis zhengi as basal to Changchengornis and Confuciusornis based on several characters. Of these, the poor development of the lateral dorsal central fossae is probably ontogenetic, as pneumaticity increases with age in saurischians. Even if it is characteristic of adults as well, it would more parsimoniously be an apomorphy, since Sapeornis and ornithothoracines both have deep fossae like Confuciusornis and Changchengornis. The low acromion is similarly perhaps caused by ontogeny, as that of the juvenile Zhongornis is similar. Again, this would be just as likely to be an apomorphy of zhengi, since ornithothoracines have prominent acromions like Confuciusornis and Changchengornis. The short coracoid is more likely to be an apomorphy, since Shenzhouraptor, Jixiangornis and some Sapeornis specimens have elongate coracoids. The coracoid foramen is not known to be absent in Changchengornis, so its absence remains an apomorphy of Confuciusornis sanctus. The pubic boot is not known to be absent in Changchengornis. The low deltopectoral crest may be ontogenetic, as this is true in enantiornithines. The elongate astragalar ascending process is found in all coelurosaurs, and is only not apparent in Confuciusornis and Changchengornis because of their completely fused tibiotarsi. The lack of fusion in zhengi is ontogenetic, as more basal ornithurines have tibiotarsi. Additional characters are listed in the text as differing from other confuciusornithids, including some that could be attributed to ontogeny (hypocleidial swelling absent; poorly ossified sternum) and which are within the range of variation of Confuciusornis (ventral tubercle of humerus not pointed- GMV-2132).
Contrary to this hypothesis, I believe zhengi is more closely related to Confuciusornis than either is to Changchengornis. This is based on the enlarged surangular foramen, furcular arm width which is >20% of arm length, and bowed manual phalanx II-2. In fact, the first character is only found in C. sanctus, not C. dui. The only character which would place zhengi outside Confuciusornis (sanctus + dui) is the absent humeral foramen, but this may be ontogenetic and seems to be developing as a fossa in the specimen. The dorsal maxillary process appears narrow and vertical in the figure, as in C. dui, but Zhang et al. note this may be the anterior margin of a broader process instead. It seems more parsimonious to place Eoconfuciusornis zhengi within Confuciusornis as C. zhengi, unless C. dui is to be assigned its own genus.
References- Chiappe, Marugan-Lobon, Ji and Zhou, 2008. Life history of a basal bird: morphometrics of the Early Cretaceous Confuciusornis. Biology Letters. 4(6), 719-723.
Jin, Zhang, Li, Zhang, Li and Zhou, 2008. On the horizon of Protopteryx and the early vertebrate fossil assemblages of the Jehol Biota. Chinese Science Bulletin. 53(18), 2820-2827.
Zhang, Zhou and Benton, 2008. A primitive confuciusornithid bird from China and its implications for early avian flight. Science in China Series D: Earth Sciences. 51(5), 625-639.
C. sanctus Hou, Zhou, Gu and Zhang, 1995
= Confuciusornis suniae Hou, 1997
= Jinzhouornis zhangjiyingia Hou, Zhou, Zhang and Gu, 2002
= Jinzhouornis yixianensis Hou, Zhou, Zhang and Gu, 2002
Late Barremian-Early Aptian, Early Cretaceous
Jianshangou Beds of Yixian Formation, Liaoning, China
Holotype- (IVPP V10918) skull (50 mm), mandible, humerus (49.6 mm), radius (45.77 mm), ulna (42 mm), radiale, ulnare, metacarpal I (9 mm), phalanx I-1, manual ungual I, carpometacarpus (II 22.5 mm, III 19 mm), phalanx II-1 (21 mm), proximal phalanx II-2, phalanx III-1 (5 mm), phalanx III-2 (14 mm), proximal phalanx III-3, manual claw sheath
Paratypes- ?(IVPP V10895) partial ilium, proximal pubis, proximal ischium, femur (33 mm), incomplete tibiotarsus (41 mm), fibular fragment, tarsometatarsus (20 mm), partial phalanx II-1 (7 mm), phalanx II-2 (5.2 mm), pedal ungual II (6.5 mm), phalanx III-1 (6 mm), phalanx III-2 (5 mm), phalanx III-3 (5 mm), pedal ungual III (8 mm), phalanx IV-1 (4 mm), phalanx IV-2 (3 mm), phalanx IV-3 (3 mm), phalanx IV-4 (4.5 mm), pedal ungual IV (7 mm), metatarsal V (8 mm), pedal claw sheaths, body feathers
?(IVPP V10920) feathers
?(IVPP V10921) feathers
?(IVPP V10922) feathers
?(IVPP V10923) feathers
?(IVPP V10924) feathers
?(IVPP V10925) feathers
Referred- (BPV 2066) skull, partial mandibles, two cervical vertebrae, two dorsal vertebrae, dorsal ribs, synsacrum, caudal vertebrae, pygostyle, scapulocoracoids, furcula, humeri (51.57 mm), radii (one incomplete; 42.53 mm), ulnae (one incomplete; 45.39 mm), metacarpals I, phalanges I-1 (one partial), manual ungual I, carpometacarpi, phalanges II-1, proximal phalanges II-2, phalanx III-1, distal phalanx III-2, phalanges III-3, manual unguals III, incomplete pubes, incomplete femora (43.65 mm), incomplete tibiotarsi (53.03 mm), fibulae, phalanges I-1, pedal unguals I, tarsometatarsi, phalanges II-1, phalanges II-2, pedal unguals II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV (Guan et al., 1997)
(BSP 1999 I 15) (male) specimen including humerus (68.55 mm), radius (57.8 mm), ulna (58.04 mm), femur (59.47 mm), tibiotarsus (70.24 mm) and retrices (Chiappe et al., 2008)
(CAGS 1) (male) specimen including humerus (55.08 mm), radius (49.67 mm), femur (43.66 mm), tibiotarsus (47.73 mm) and retrices (Chiappe et al., 2008)
(D1196) (male) specimen including humerus (53.16 mm), radius (41.36 mm), ulna (46.5 mm), tibiotarsus (52.54 mm) and retrices (Chiappe et al., 2008)
(D2151) (female) specimen including humerus (66.9 mm), radius (50.39 mm), ulna (53.83 mm), femur (50.94 mm) and tibiotarsus (63.16 mm) (Chiappe et al., 2008)
(D2859) (male) specimen including humerus (51.8 mm), radius (42.23 mm), ulna (44.83 mm), femur (43.93 mm), tibiotarsus (50.82 mm) and retrices (Chiappe et al., 2008)
(D2860) (male) specimen including humerus (53.75 mm), ulna (46.84 mm), femur (44.04 mm), tibiotarsus (54.76 mm) and retrices (Chiappe et al., 2008)
(GMV 1) (male) specimen including humerus (49.8 mm), radius (43.1 mm), ulna (45.2 mm), femur (43.8 mm), tibiotarsus (50.4 mm) and retrices (Chiappe et al., 2008)
(GMV 2) (male) specimen including humerus (51.25 mm), radius (42.6 mm), ulna (44.6 mm), femur (42.4 mm), tibiotarsus (52.95 mm) and retrices (Chiappe et al., 2008)
(GMV 6) specimen including humerus (52.86 mm), radius (43.17 mm) and femur (44.74 mm) (Chiappe et al., 2008)
(GMV 7) specimen including femur (55.91 mm) (Chiappe et al., 2008)
(GMV 8) (male) specimen including humerus (53.25 mm), radius (43.9 mm), ulna (45.3 mm), femur (45.7 mm), tibiotarsus (52.1 mm) and retrices (Chiappe et al., 2008)
(GMV 9) (male) specimen including humerus (50.95 mm), radius (43.15 mm), femur (44.5 mm), tibiotarsus (52.2 mm) and retrices (Chiappe et al., 2008)
(GMV 14) (male) specimen including humerus (50.2 mm), radius (44.2 mm), ulna (46.2 mm), femur (44 mm), tibiotarsus (52.2 mm) and retrices (Chiappe et al., 2008)
(GMV 15) (male) specimen including humerus (61.8 mm), ulna (54.5 mm), tibiotarsus (64.3 mm) and retrices (Chiappe et al., 2008)
(GMV 16) (male) specimen including humerus (48.55 mm), radius (38.7 mm), ulna (40 mm) and retrices (Chiappe et al., 2008)
(GMV 16) specimen including humerus (47.08 mm) and radius (37.17 mm) (Chiappe et al., 2008)
(GMV 19) (female) specimen including humerus (62 mm), radius (48.5 mm), ulna (52 mm), femur (51.5 mm) and tibiotarsus (59.3 mm) (Chiappe et al., 2008)
(GMV 20-1) (male) specimen including humerus (52.85 mm), radius (44.6 mm), ulna (46.9 mm), femur (43.95 mm), tibiotarsus (53.7 mm) and retrices (Chiappe et al., 2008)
(GMV 20-2) (male) specimen including humerus (69.5 mm), radius (52.1 mm), ulna (58.6 mm), femur (54.8 mm), tibiotarsus (66.35 mm) and retrices (Chiappe et al., 2008)
(GMV 21-1) (male) specimen including humerus (64.6 mm), radius (51.9 mm), ulna (52.4 mm), tibiotarsus (63.3 mm) and retrices (Chiappe et al., 2008)
(GMV 25) (male) specimen including humerus (60.45 mm), radius (50.7 mm), ulna (53.5 mm), femur (53 mm), tibiotarsus (58.1 mm) and retrices (Chiappe et al., 2008)
(GMV 26) (male) specimen including humerus (65.7 mm), radius (52.3 mm), ulna (54.8 mm), femur (56.1 mm), tibiotarsus (66.4 mm) and retrices (Chiappe et al., 2008)
(GMV 30) (male) specimen including humerus (40.85 mm), ulna (35.8 mm), femur (33.4 mm), tibiotarsus (40.9 mm) and retrices (Chiappe et al., 2008)
(GMV 32) (male) specimen including humerus (54.95 mm), radius (43.8 mm), tibiotarsus (56.4 mm) and retrices (Chiappe et al., 2008)
(GMV 33) (male) specimen including humerus (58.5 mm), radius (50.2 mm), ulna (52.1 mm), femur (52.9 mm), tibiotarsus (63.1 mm) and retrices (Chiappe et al., 2008)
(GMV 36) (male) specimen including humerus (55 mm), radius (44.2 mm), ulna (47.35 mm), femur (48 mm), tibiotarsus (53.7 mm) and retrices (Chiappe et al., 2008)
(GMV 39) (male) specimen including humerus (63.7 mm), femur (53.95 mm), tibiotarsus (64.8 mm) and retrices (Chiappe et al., 2008)
(GMV 40) (male) specimen including humerus (56.3 mm), radius (44.2 mm), ulna (47.2 mm), femur (45.45 mm), tibiotarsus (54.1 mm) and retrices (Chiappe et al., 2008)
(GMV 41) specimen including humerus (62.57 mm), radius (52.08 mm), ulna (54.38 mm), femur (53.16 mm) and tibiotarsus (61.6 mm) (Chiappe et al., 2008)
(GMV 43) (male) specimen including humerus (67.2 mm), radius (54.6 mm), femur (54.6 mm), tibiotarsus (66.5 mm) and retrices (Chiappe et al., 2008)
(GMV 44) (male) specimen including humerus (52.1 mm), radius (42.45 mm), ulna (44.8 mm), femur (44.9 mm), tibiotarsus (55 mm) and retrices (Chiappe et al., 2008)
(GMV 46) (female) specimen including humerus (66.9 mm), radius (52.55 mm), ulna 56.1 mm), femur (55.4 mm) and tibiotarsus (67 mm) (Chiappe et al., 2008)
(GMV 50) (male) specimen including humerus (62.9 mm), radius (52.75 mm), ulna (56.2 mm), femur (54.45 mm), tibiotarsus (63.8 mm) and retrices (Chiappe et al., 2008)
(GMV 52) (male) specimen including humerus (52.7 mm), radius (43.7 mm), ulna (45.4 mm), tibiotarsus (53.7 mm) and retrices (Chiappe et al., 2008)
(GMV 53) (male) specimen including humerus (67.65 mm), radius (55.85 mm), ulna (60.6 mm), femur (55.6 mm), tibiotarsus (65.6 mm) and retrices (Chiappe et al., 2008)
(GMV 54) (male) specimen including humerus (67.7 mm), radius (53.6 mm), ulna (57.45 mm), femur (55.9 mm), tibiotarsus (65.75 mm) and retrices (Chiappe et al., 2008)
(GMV 55-1) (male) specimen including humerus (69.25 mm), radius (57.25 mm), ulna (59.15 mm), femur (57.5 mm), tibiotarsus (66.6 mm) and retrices (Chiappe et al., 2008)
(GMV 56-1) (male) specimen including humerus (50.1 mm), radius (41.3 mm), ulna (45.5 mm), femur (42.8 mm), tibiotarsus (51.95 mm) and retrices (Chiappe et al., 2008)
(GMV 56-2) (male) specimen including humerus (51.1 mm), radius (43.2 mm), ulna (45.25 mm), femur (44.5 mm), tibiotarsus (53.55 mm) and retrices (Chiappe et al., 2008)
(GMV 59-1) (male) specimen including humerus (65.75 mm), radius (53.1 mm), ulna (57 mm), femur (55.7 mm), tibiotarsus (67.25 mm) and retrices (Chiappe et al., 2008)
(GMV 59-2) (male) specimen including humerus (63.75 mm), radius (49.8 mm), ulna (54.45 mm), femur (55 mm), tibiotarsus (61.1 mm) and retrices (Chiappe et al., 2008)
(GMV 60) (male) specimen including humerus (52.9 mm), radius (43.7 mm), ulna (44.9 mm), femur (43.7 mm) and retrices (Chiappe et al., 2008)
(GMV 61) (male) specimen including femur (47.6 mm), tibiotarsus (60.7 mm) and retrices (Chiappe et al., 2008)
(GMV 62) (male) specimen including humerus (61.6 mm), ulna (51.35 mm), femur (53.7 mm), tibiotarsus (64.1 mm) and retrices (Chiappe et al., 2008)
(GMV 66-1) (male) specimen including humerus (51.9 mm), ulna (45.1 mm), femur (43.9 mm), tibiotarsus (53.05 mm) and retrices (Chiappe et al., 2008)
(GMV 66-2) (male) specimen including humerus (65.45 mm), radius (51.8 mm), ulna (55.4 mm), femur (52.95 mm), tibiotarsus (63.7 mm) and retrices (Chiappe et al., 2008)
(GMV 67-1) (male) specimen including humerus (66.3 mm), radius (57.2 mm), femur (54.05 mm), tibiotarsus (66.15 mm) and retrices (Chiappe et al., 2008)
(GMV 67-2) (female) specimen including humerus (52.4 mm), radius (42.9 mm) and tibiotarsus (49.5 mm) (Chiappe et al., 2008)
(GMV 69-1) (male) specimen including humerus (64 mm), radius (51.7 mm), ulna (55.4 mm), femur (51.9 mm), tibiotarsus (61.5 mm) and retrices (Chiappe et al., 2008)
(GMV 69-2) (male) specimen including humerus (64.5 mm), radius (51.8 mm), ulna (54.2 mm), femur (51.8 mm), tibiotarsus (61.5 mm) and retrices (Chiappe et al., 2008)
(GMV 73) (male) specimen including humerus (58.85 mm), radius (48.75 mm), ulna (50.7 mm), femur (48.4 mm), tibiotarsus (57.85 mm) and retrices (Chiappe et al., 2008)
(GMV 77) (male) specimen including humerus (56.15 mm), radius (45.65 mm), femur (47.9 mm), tibiotarsus (54.85 mm) and retrices (Chiappe et al., 2008)
(GMV 78) specimen including ulna (44.63 mm) (Chiappe et al., 2008)
(GMV 101) specimen including radius (36.63 mm), femur (34.38 mm) and tibiotarsus (39.21 mm) (Chiappe et al., 2008)
(GMV 2130; 2030 in Chiappe et al., 2008) (female) skull, sclerotic ossicles, mandible, cervical vertebrae, at least eight dorsal vertebrae, dorsal ribs, uncinate processes, synsacrum, caudal vertebrae, pygostyle, proximal scapula, incomplete sternum, nine sternal ribs, humeri (47.86, 47.69 mm), radii (38.87 mm), ulnae (40.73 mm), radiale, ulnare, metacarpals I (5.99 mm), phalanges I-1, manual unguals I, carpometacarpi (II 21.11 mm), phalanges II-1, phalanges II-2 (one proximal), phalanges III-2, phalanges III-3, manual claw sheaths, partial ilia, femora (one proximal; 41.78 mm), tibiotarsus (48.70 mm), metatarsals I (5.48, 5.5 mm), phalanx I-1, pedal ungual I, tarsometatarsi (23.21, 23.28 mm), phalanges II-1, phalanges II-2, pedal unguals II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, pedal claw sheaths, body feathers, remiges (to 210 mm) (Chiappe et al., 1999)
(GMV 2131; 2031 in Chiappe et al., 2008) (male) skull, partial mandible, partial hyoids, seven cervical vertebrae, twelve dorsal vertebrae, dorsal ribs, synsacrum, five caudal vertebrae, pygostyle, furcula, partial sternum, five sternal ribs, humeri (~40.01, 41.86 mm), radii (35.21, 34.89 mm), ulnae (35.05 mm), metacarpals I (~6.45 mm), phalanges I-1, manual unguals I, carpometacarpi (II 20.78, III 18.38 mm), phalanges II-1, phalanx II-2, manual ungual II, phalanges III-2, phalanx III-3, manual ungual III, manual claw sheaths, partial ilia, femoral fragments, partial tibiotarsi, metatarsals I (4.43 mm), phalanges I-1, pedal unguals I, tarsometatarsi (20.52, 20.65 mm), phalanges II-1, phalanges II-2, pedal unguals II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, pedal claw sheaths, body feathers, remiges, retrices (Chiappe et al., 1999)
(GMV 2132) skull, scerlotic plates, mandible, six cervical vertebrae, twelve dorsal vertebrae, dorsal ribs, gastralia, three caudal vertebrae, pygostyle, proximal scapulae, coracoids, furcula, humeri (68.10, 69.15 mm), radii (56.55, 56.53 mm), ulnae (58.45 mm), radiales, ulnare, metacarpals I (11.66, 11.51 mm), phalanges I-1, manual unguals I, carpometacarpi (II 32.86, 33.15 mm, III 25.54, 25.91 mm), phalanges II-1, phalanges II-2, manual unguals II, phalanx III-1, phalanges III-2, phalanges III-3, manual unguals III, partial ilium, pubes, femora (55.63 mm), tibiotarsi (one incomplete; 66.05 mm), fibula, proximal tarsometatarsus (Chiappe et al., 1999)
(GMV 2133) (male) skull, sclerotic ring, mandibles, six cervical vertebrae, two dorsal vertebrae, dorsal ribs, synsacrum, seven caudal vertebrae, pygostyle (32 mm), scapulae, coracoids, furcula, humeri (52.58, 53.53 mm), radii (43.65 mm), ulnae (45.38 mm), radiale, metacarpal I, phalanx I-1, proximal carpometacarpus, phalanx II-1, phalanx II-2, manual unguals II, phalanges III-2, phalanx III-3, ilia, pubes, ischia, femora (46.85 mm), tibiotarsi (53.29, 52.99 mm), fibulae (one partial), metatarsals I (6.48 mm), phalanges I-1, pedal unguals I, tarsometatarsi (25.64, 25.48 mm), phalanges II-1, phalanges II-2, pedal unguals II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, pedal claw sheaths, metatarsals V, body feathers, remiges, retrices (Chiappe et al., 1999)
(GMV 2141) distal tibiotarsus, metatarsal I, phalanx I-1, pedal ungual I, tarsometatarsus, phalanx II-1, phalanx II-2, pedal ungual II, phalanx III-1, phalanx III-2, phalanx III-3, pedal ungual III, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV (Chiappe et al., 1999)
(GMV 2142) incomplete skeleton (Chiappe et al., 1999)
(GMV 2146) (male) specimen including skull, mandibles, cervical vertebrae, uncinate processes, seven caudal vertebrae, humeri (41.95, 42.69 mm), radius (34.68 mm), ulna (35.62 mm), manus, remiges, retrices (Chiappe et al., 1999)
(GMV 2147) (male) specimen including anterior cervical vertebrae, cervical ribs, at least eight dorsal vertebrae, dorsal ribs, uncinate processes, partial sternum, eight sternal ribs, humeri (41.35, 42.24 mm), manual ungual, retrices (Chiappe et al., 1999)
(GMV 2148) specimen including skull, mandible, cervical vertebrae, dorsal vertebrae, dorsal ribs, scapulocoracoid, furcula, humeri, radii, ulnae, metacarpal I, phalanx I-1, manual ungual I, carpometacarpi, phalanx II-1, phalanx II-2, manual ungual II, phalanx III-1, phalanges III-2, phalanges III-3, manual ungual III, pubes (one partial), femora, proximal tibiotarsi, body feathers (Chiappe et al., 1999)
(GMV 2149) specimen including dorsal vertebrae, dorsal ribs, six uncinate processes, gastralia, humerus (53.52 mm), manual ungual, femora (45.45, 44.48 mm) (Chiappe et al., 1999)
(GMV 2150) (male) specimen including skull, mandibles, cervical vertebrae, dorsal vertebrae, pygostyle, coracoids, humeri (~50.82, 51.54 mm), radii (39.9 mm), ulnae (44.05 mm), radiale, metacarpal I, phalanx I-1, carpometacarpi (one partial), phalanges II-1, phalanx II-2, ilium, femur (44.96 mm), incomplete tibiotarsus (51.2 mm), body feathers, remiges, retrices (270 mm) (Chiappe et al., 1999)
(GMV 2151) (female) specimen including humerus (50.88 mm), manus, femora (43.74, 44.09 mm) and remiges (Chiappe et al., 1999)
(GMV 2152) specimen including gastralia, sternal fragment and femur (Chiappe et al., 1999)
(GMV 2153-1) (male) specimen including skull, four cervical vertebrae, dorsal vertebrae, dorsal ribs, synsacrum, pygostyle, furcula, humeri (52.9 mm), radii (41.55 mm), ulnae (44.2 mm), radiales, metacarpals I, phalanges I-1, manual unguals I, carpometacarpi, phalanges II-1, phalanges II-2 (one proximal), phalanges III-1, phalanges III-2, phalanges III-3, manual unguals III, partial ilia, pubes, femora (45.19, 45.3 mm), tibiotarsi (54.5 mm), tarsometatarsus, pedal phalanges, body feathers, retrices (Chiappe et al., 1999)
(GMV 2153-2) (male) specimen including skull, mandible, cervical vertebrae, dorsal vertebrae, dorsal ribs, gastralia, synsacrum, seven caudal vertebrae, pygostyle, scapula, coracoid, partial furcula, partial sternum sternal ribs, humeri (44.28, 45.15 mm), radii (36.7 mm), ulna (39 mm), ilia, femora (37.72 mm), distal tibiotarsus, tarsometatarsus, phalanx II-1, phalanx II-2, pedal ungual II, phalanx III-1, phalanx III-2, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, three pedal unguals, body feathers, retrices (Chiappe et al., 1999)
(GMV 2154) (male) specimen including sternal ribs, humeri (63.14, 64.19 mm), radius (52.05 mm), ulna (53.4 mm), femora (51.72, 53.08 mm), tibiotarsus (63 mm), tarsometatarsus, retrices (Chiappe et al., 1999)
(GMV 2155) (male) specimen including humeri (~51.38, 52.16 mm), radius (43 mm), femora (44.51, 45.79 mm), tibiotarsus (52.85 mm), retrices (Chiappe et al. 1999)
(GMV coll.) nearly 37 more specimens (Chiappe et al. 1999)
(IVPP V100921) (female) specimen including humerus (55.76 mm), radius (48.72 mm), ulna (49.58 mm), femur (45.58 mm) and tibiotarsus (53.46 mm) (Chiappe et al., 2008)
(IVPP V10928) specimen including sternum (Zhang et al., 2008)
(IVPP V11308; holotype of Confuciusornis suniae) skull, sclerotic ring, mandibles, hyoids, nine cervicals (6 is 8 mm), partial cervical rib, ten dorsal vertebrae (8 is 5 mm), dorsal ribs, four uncinate processes(?), gastralia, sacrum (50 mm), ten caudal vertebrae, pygostyle, scapulae (42.5 mm), proximal coracoid, partial furcula, sternum (43 mm), sternal ribs, humerus (53.18 mm), radius (45.96 mm), ulna (46.46 mm), radiales, ulnares, distal carpal III, metacarpals I (8 mm), phalanges I-1 (one proximal; 19 mm), manual ungual I, carpometacarpi (one incomplete; II 25.5 mm, III 18 mm), phalanges II-1 (18.5 mm), phalanges II-2 (20 mm), manual ungual II (8 mm), phalanx III-1 (5 mm), phalanx III-2 (14 mm), phalanx III-3 (15 mm), manual ungual III (16 mm), manual claw sheaths, ilium (33.5 mm), pubis (47 mm), ischium, femora (46.79 mm), patella?, tibiotarsi (55.83 mm), fibulae (~41 mm), metatarsal I, phalanx I-1, pedal ungual I, metatarsal II, phalanx 2-1, phalanx II-2, pedal ungual II, metatarsal III (26 mm), phalanx III-1, phalanx III-3, pedal ungual III (10 mm), metatarsal IV, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV (12 mm), pedal claw sheaths, metatarsal V, feathers (Hou, 1997)
(IVPP V11370) (male) specimen including skull (76 mm), sacrum (35 mm), humerus (68.14 mm), radius (54.89 mm), ulna (58.21 mm), femur (58.89 mm), tibiotarsus (69.12 mm), phalanx II-1, phalanx II-2, phalanx IV-3, phalanx IV-4 and retrices (Xu et al., 2000)
(IVPP V11372) (female) specimen including humerus (52.77 mm), radius (44.62 mm), ulna (47.07 mm), femur (44.73 mm) and tibiotarsus (51.09 mm) (Chiappe et al., 2008)
(IVPP V11374) (female) specimen including humerus (51.46 mm), radius (44.4 mm), ulna (45.84 mm), femur (45.86 mm) and tibiotarsus (53.33 mm) (Hutchinson, 2001)
(IVPP V11375) (male) specimen including humerus (53.28 mm), radius (42.87 mm), ulna (44.68 mm), femur (45.74 mm), tibiotarsus (52.76 mm) and retrices (Chiappe et al., 2008)
(IVPP V11552) specimen including skull (58.5 mm), mandible, cervical vertebrae, dorsal vertebrae, dorsal ribs, uncinate processes, synsacrum (29.9 mm), pygostyle (~28.2 mm), scapulae (~49.2 mm), coracoids (~20.6 mm), furcula (21.6 mm), sternum (~42.2 mm), sternal ribs, humeri (55.5 mm), radii (48.5 mm), ulnae (51.5 mm), ulnares, metacarpals I (9.7 mm), phalanges I-1, manual unguals I (22.1 mm), carpometacarpi (II 27.5 mm, III ~25.5 mm), phalanges II-1 (20.3 mm), phalanx II-2 (21.2 mm), manual ungual II (7.8 mm), phalanges III-1 (~4.2 mm), phalanges III-2 (8.6 mm), phalanges III-3 (~18.6 mm), manual unguals III (~15 mm), manual claw sheaths, ilium (31.6 mm), pubis (45.7 mm), ischium (~25.5 mm), femur (47.6 mm), tibiotarsus (55.2 mm), fibula (30.2 mm), phalanx I-1 (5.7 mm), tarsometatarsus (29.5 mm), phalanx II-1 (6.9 mm), phalanx II-2 (8 mm), phalanx III-1 (7.9 mm), phalanx III-2 (6.5 mm), phalanx IV-1 (5 mm), phalanx IV-2 (4.2 mm), phalanx IV-3 (4.1 mm), phalanx IV-4 (4.8 mm) (Zhou, 1999)
(IVPP V11619) specimen including humerus (52 mm), ulna (47 mm), carpometacarpus (27 mm), pubis (47 mm), femur (47 mm), tibiotarsus (54 mm), tarsometatarsus (25 mm) (Zhou and Zhang, 2002)
(IVPP V11640) (male) specimen including skull, mandible, cervical vertebrae, dorsal vertebrae, dorsal ribs, sacrum, scapulae, humeri (64.94 mm), radii (50.81 mm), ulnae (54.86 mm), metacarpal I, phalanx I-1, manual ungual I, carpometacarpus (30 mm), phalanx II-1, phalanx II-2, manual claw sheath, ilia, femora (55 mm), tibiotarsi (65.42 mm), metatarsal I, phalanx I-1, pedal ungual I, tarsometatarsi (30 mm), phalanges II-1, phalanges II-2, pedal unguals II, phalanx III-1, phalanx III-2, phalanx III-3, pedal ungual III, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, peal phalanges, pedal unguals, body feathers, remiges, retrices (Hou et al., 2002)
(IVPP V11794) specimen including humerus (63.5 mm), ulna (55 mm), carpometacarpus (32 mm), femur (55 mm) and tibiotarsus (66 mm) (Hou et al., 2002)
(IVPP V11795) specimen including humerus (44 mm), ulna (37 mm), femur (36 mm) and tibiotarsus (42 mm), (Hou et al., 2002)
(IVPP V13156) (female) specimen including cervical vertebrae, dorsal vertebrae, dorsal ribs, sacrum, caudal vertebrae, pygostyle, scapula, humerus (60.97 mm), radius, ulna (53.52 mm), radiale, ulnare, metacarpal I, phalanx I-1, manual ungual I, carpometacarpus, phalanx II-1, phalanx II-2, manual ungual II, phalanx III-1, phalanx III-2, phalanx III-3, manual ungual III, manual claw sheaths, femur (53.16 mm), tibiotarsus (60.81 mm), fibula, metatarsal I, phalanx I-1, pedal ungual I, tarsometatarsus, phalanx II-1, phalanx II-2, pedal ungual II, phalanx III-1, phalanx III-2, phalanx III-3, pedal ungual III, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, pedal claw sheaths, body feathers, remiges (Zhou and Zhang, 2006)
(IVPP V12352; holotype of Jinzhouornis zhangjiyingia) (male) skull, mandible, three cervical vertebrae, seven dorsal vertebrae, dorsal ribs, pygostyle, scapula, sternum, sternal ribs, humeri (53.8 mm), radii, ulnae (45.39 mm), radiale, ulnare, metacarpals I, phalanges I-1, manual unguals I, carpometacarpi, phalanges II-1, phalanges II-2, manual unguals II, phalanx III-1, phalanx III-2, phalanges III-3, manual unguals III, manual claw sheaths, femora (41.78 mm), tibiotarsi (49.11 mm), metatarsals I, phalanges I-1, pedal unguals I, tarsometatarsi, phalanges II-1, phalanges II-2, pedal unguals II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, retrices (Hou et al., 2002)
(IVPP V110304) skull (73 mm), sclerotic ring, mandible (62 mm), hyoids, atlas, axis, cervical vertebrae 3-9, cervical ribs, anterior dorsal vertebra, dorsal ribs, gastralia, caudal vertebra, scapula (52 mm), coracoid (28 mm), furcula (27 mm across), sternum (45 mm), humeri (one proximal; 61 mm), radius (52 mm), ulna (55 mm), radiale, ulnare, metacarpal I (11 mm), phalanx I-1 (19 mm), manual ungual I (16.5 mm), carpometacarpus (II 32.5 mm, III 31 mm), phalanx II-1, phalanx II-2, manual ungual II (8 mm), phalanx III-2, phalanx III-3, manual ungual III (21 mm), proximal femur, tibiotarsi (66 mm), fibula (35 mm) proximal tarsometatarsus, remiges (Hou et al., 1996)
(IVPP coll.) specimen including skull, mandible, cervical vertebrae, dorsal vertebrae, dorsal ribs, pygostyle, radius, ulna, manus, pubis, femur, tibiotarsus, pedal digit I, tarsometatarsus, pedal digit II, pedal digit III, pedal digit IV, feathers (Hou et al., 1996)
(IVPP coll.) specimen including skull, mandible, cervical vertebrae, dorsal vertebrae, caudal vertebrae, furcula, humerus, radius, ulna, manus, femora, tibiotarsi, trsometatarsi, pedal phalanges, pedal unguals (Hou et al., 1996)
(IVPP coll.) specimen including gastralia, pygostyle, furcula, sternum, humerus, radius, ulna, manus, pubes, femora, tibiotarsi, tarsometatarsi, pedal digits, remiges (Hou et al., 1996)
?(IVPP coll.) remiges (Hou et al., 1996)
(IVPP coll.) four specimens with skulls (Hou et al., 1996)
?(IVPP coll.) many feathers (Hou, 1997)
(IVPP coll.; holotype of Jinzhouornis yixianensis) skull, partial mandible, cervical vertebrae, dorsal vertebrae, dorsal ribs, partial pygostyle, scapulae (one incomplete), incomplete humeri, incomplete radii, ulnae (one incomplete, one partial), radiale, metacarpal I, phalanx I-1, manual ungual I, carpometacarpi (one proximal), phalanx III-1, incomplete phalanx III-3, partial manual ungual III, manual claw sheath, partial femora (~40 mm), tibiotarsi (one distal; ~50 mm), metatarsals I, phalanges I-1, pedal unguals I, tarsometatarsi (~24 mm), phalanx II-1, phalanges II-2, pedal unguals II, phalanx III-1, phalanges III-2, phalanx III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV (Hou et al., 2002)
(JM-UKr-1996/15) skeleton including radius (53.55 mm), ulna (55.81 mm), femur (55.4 mm) and tibiotarsus (62.4 mm) (Viohl, 1997)
(JM-UKr-1997/1) skeleton including skull, mandible, six cervical vertebrae, dorsal vertebrae, dorsal ribs, synsacrum, humerus (51.79 mm), radius (43.9 mm), ulna (46.6 mm), radiale, ulnare, metacarpal I, phalanx I-1, manual ungual I, carpometacarpus, phalanx II-1, phalanx II-2, manual ungual II, phalanx III-1, phalanx III-2, phalanx III-3, manual ungual III, femur (46.1 mm), tibiotarsus (53.29 mm), feathers (Viohl, 1997)
(JM-UKr-2005/1) (male) specimen including humerus (59.31 mm), radius (44.4 mm), ulna (46.68 mm), femur (44.08 mm), tibiotarsus (54 mm) and retrices (Chiappe et al., 2008)
(LACM 153346) specimen including humerus (59.51 mm), radius (50.75 mm), ulna (51.65 mm), femur (55.43 mm) and tibiotarsus (63.56 mm) (Chiappe et al., 2008)
(LPM 0012) (male) specimen including humerus (50 mm), radius (42.94 mm), ulna (41.2 mm), femur (45.03 mm), tibiotarsus (53.24 mm) and retrices (Chiappe et al., 2008)
(LPM 0228A) (female) specimen including ulna (54.39 mm), femur (50.87 mm) and tibiotarsus (63.98 mm) (Chiappe et al., 2008)
(LPM 0228B) (female) specimen including humerus (60.89 mm), ulna (49.18 mm) and femur (51.71 mm) (Chiappe et al., 2008)
(LPM 0228C) (female) specimen including humerus (61.15 mm), radius (50.96 mm), ulna (55.6 mm), femur (55.19 mm) and tibiotarsus (63.96 mm) (Chiappe et al., 2008)
(LPM 0229 right) (male) specimen including humerus (47.43 mm), radius (38.03 mm), ulna (37.95 mm), femur (43.34 mm), tibiotarsus (51.69 mm) and retrices (Chiappe et al., 2008)
(LPM 0229 left) (male) specimen including humerus (57.23 mm), radius (46.86 mm), ulna (49.42 mm), femur (47.12 mm), tibiotarsus (58.2 mm) and retrices (Chiappe et al., 2008)
(LPM 0233) (male) specimen including humerus (41.01 mm), femur (32.44 mm), tibiotarsus (36.85 mm) and retrices (Chiappe et al., 2008)
(LL.12418) specimen including humerus (50.06 mm), radius (41.1 mm), ulna (42.93 mm), femur (44.93 mm) and tibiotarsus (49.76 mm) (Chiappe et al., 2008)
(MB Av.1168-1171) (female) specimen including humerus (45.51 mm), ulna (41.72 mm), femur (41.71 mm) and tibiotarsus (48.88 mm) (Chiappe et al., 2008)
(MCFO-0374) (male) specimen including humerus (47.54 mm), radius (38 mm), ulna (41 mm), femur (41.4 mm), tibiotarsus (46.85 mm) and retrices (Chiappe et al., 2008)
(MCFO-0589A) (male) specimen including humerus (61.66 mm), radius (52.37 mm), ulna (56.27 mm), femur (53.21 mm), tibiotarsus (64.34 mm) and retrices (Chiappe et al., 2008)
(MCFO-0589B) (male) specimen including ulna (59.14 mm), femur (56.28 mm), tibiotarsus (66.64 mm) and retrices (Chiappe et al., 2008)
(NBM 258) (female) specimen including humerus (51.75 mm), radius (41.15 mm), ulna (44.05 mm), femur (43.44 mm) and tibiotarsus (52.09 mm) (Chiappe et al., 2008)
(NGMC 98-8-2; MOR 1063) (adult) dorsal vertebrae, few dorsal ribs, gastralia, synsacrum, caudal vertebrae, pygostyle, coracoid, humeri, radii, ulnae, radiales, metacarpals I, phalanges I-1, manual unguals I, carpometacarpi, phalanges II-1 (one proximal), phalanx II-2, manual ungual II, phalanx III-2, incomplete phalanges III-3, manual unguals III, pubes, ischium, femora, tibiotarsi, metatarsal I, phalanx I-1, pedal ungual I, tarsometatarsi, phalanges II-1, phalanges II-2, pedal unguals II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, metatarsal V (de Ricqles et al., 2003)
(NHMW1997z/0000) (female) specimen including humerus (66.4 mm), radius (56.81 mm), ulna (57.37 mm), femur (55.23 mm) and tibiotarsus (66.67 mm) (Chiappe et al., 2008)
(NHMW1997z/0112) specimen including cervical vertebrae, dorsal ribs, scapulocoracoid, humerus, radius, ulna, metacarpal I, phalanx I-1, manual ungual I, carpometacarpus, phalanx Ii-1, phalanx II-2, manual ungual II, phalanx III-2, phalanx III-3, manual ungual III, body feathers and remiges (Peters and Ji, 1999)
(PMO.161.632) (female) specimen including humerus (50.88 mm), radius (39.9 mm), ulna (45.22 mm), femur (42.65 mm) and tibiotarsus (51.87 mm) (Chiappe et al., 2008)
(RTMP 981401) (male) specimen including humerus (62.77 mm), radius (51.99 mm), ulna (53.93 mm), femur (52.43 mm), tibiotarsus (63.33 mm) and retrices (Chiappe et al., 2008)
(RTMP 981402) (male) specimen including humerus (51.33 mm), femur (46.7 mm), tibiotarsus (52.67 mm) and retrices (Chiappe et al., 2008)
(SMFAv-412) skeleton including atlas, axis, postaxial cervical vertebrae, humerus, radius, ulna (42.81 mm), radiale, ulnare, metacarpal I, phalanx I-1, carpometacarpus, femur (43.73 mm) and tibiotarsus (50.4 mm) (Peters, 1996)
(SMFAv-416) (male) skeleton including skull, mandible, humerus (65.29 mm), radius (54.58 mm), ilium, femur (54.53 mm), tibiotarsus (63.64 mm) and retrices (Peters, 1996)
(SMFAv-417) specimen including humerus (50.73 mm), radius (40.49 mm), ulna (43.85 mm), femur (46.73 mm) and tibiotarsus (53,68 mm) (Chiappe et al., 2008)
(SMFAv-419) (female) specimen including humerus (41.3 mm) and ulna (38.51 mm) (Chiappe et al., 2008)
(SMFAv-420) specimen including femur (55.97 mm) (Chiappe et al., 2008)
(SMFAv-421) skeleton including tarsometatarsus (Peters, 1996)
(SMFAv-423) skeleton including cervical vertebrae, dorsal vertebrae, dorsal ribs, sacapulocoracoids, furcula, sternum, sternal ribs, femur, tarsometatarsus (Peters, 1996)
(SMNK-Pal.6413) specimen including humerus (48.31 mm), radius (40.32 mm), ulna (42.16 mm) and tibiotarsus (51.57 mm) (Chiappe et al., 2008)
(private coll.; Bonn specimen) skull, mandible, hyoids, eight cervical vertebrae, five dorsal vertebrae, dorsal ribs, gastralia, synsacrum, seven caudal vertebrae, two chrevrons, pygostyle, scapulocoracoids, furcula, sternum, humeri, radii, ulnae, radiales, ulnares, metacarpals I, phalanges I-1, manual unguals I, carpometacarpi, phalanges II-1, phalanges II-2, manual ungual II, phalanx III-1, phalanges III-2, phalanges III-3, manual unguals III, manual claw sheaths, ilia, pubes, ischium, femora, tibiotarsi, fibula, metatarsals I, phalanges I-1, pedal unguals I, tarsometatarsi, phalanx II-1, phalanx II-2, pedal unguals II, phalanx III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, pedal claw sheaths, metatarsal V, body feathers, remiges (Goernemann, 1999)
(male) specimen including skull, mandible, cervical vertebrae, dorsal ribs, sacrum, pygostyle, scapulae, coracoids, humeri, radii, ulnae, metacarpal I, carpometacarpus, phalanx II-1, phalanx II-2, phalanx III-2, phalanx III-3, manual ungual III, ilia, femora, tibiotarsi, tarsometatarsi, pedal phalanges, pedal unguals, body feathers, remiges, retrices (Martin et al., 1998)
several hundred specimens (Martin et al., 1998)
specimen including skull, mandible, five cervical vertebrae, dorsal vertebrae, dorsal ribs, gastralia, synsacrum, caudal vertebrae, pygostyle, scapulae, humeri, radii, ulnae, metacarpal I, phalanx I-2, manual ungual I, carpometacarpi, phalanx II-1, phalanx III-2, phalanx III-3, manual ungual III, manual claw sheath, ilia, distal pubes, femora, tibiotarsi, fbulae, metatarsals I, phalanges I-1, pedal unguals I, tarsometatarsi, phalanx II-1, phalanx II-2, pedal ungual II, phalanx III-1, phalanx III-2, phalanx III-3, pedal ungual III, phalanx IV-1, phalanx IV-2, phalanx IV-3, phalanx IV-4, pedal ungual IV, pedal phalanges, pedal unguals, body feathers, remiges (Paul, 2002)
specimen including skull, mandible, seven cervical vertebrae, dorsal vertebrae, dorsal ribs, uncinate processes, gastralia, synsacrum, caudal vertebrae, pygostyle, scapulocoracoids, humeri, radii, ulnae, radiale, metacarpals I, phalanges I-1, manual ungual I, carpometacarpi, phalanges II-1, phalanges II-2, manual unguals II, phalanges III-1, phalanges III-2, phalanges III-3, manual unguals III, ilia, distal pubes, femora, tibiotarsi, metatarsal I, phalanges I-1, pedal unguals I, tarsometatarsi, phalanges II-1, phalanges II-2, pedal unguals II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, body feathers, remiges (Paul, 2002)
(male) specimen including skull, mandible, sclerotic ring, cervical vertebrae, dorsal vertebrae, dorsal ribs, synsacrum, caudal vertebrae, pygostyle, scapulocoracoids, furcula, humeri, radii, ulnae, radiales, ulnare, metacarpals I, phalanges I-1, manual unguals I, carpometacarpi, phalanges II-1, phalanges II-2, manual unguals II, phalanges III-1, phalanges III-2, phalanges III-3, manual unguals III, manual claw sheaths, ilium, pubes, femora, tibiotarsi, metatarsal I, phalanx I-1, tarsometatarsi, phalanges II-1, phalanges II-2, pedal unguals II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanges IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, pedal claw sheaths, body feathers, remiges, retrices (Paul, 2002)
skull, mandibles, hyoids (Paul, 2002)
Early Albian, Early Cretaceous
Jiufotang Formation, Liaoning, China
?(IVPP V13313) skull, mandible, ten cervical vertebrae, cervical ribs, over eight dorsal vertebrae, dorsal ribs, synsacrum, four caudal vertebrae, chevrons, scapulocoracoids, furcula, sternum, humeri (58 mm), radii, ulnae (49 mm), metacarpal I, phalanges I-1, manual ungual I, carpometacarpi, phalanges Ii-1, phalanges II-2, manual unguals II, phalanges III-1, phalanges III-2, phalanges III-3, manual unguals III, manual claw sheath, ilium, pubes, ischia (one proximal), femora (47 mm), tibiotarsi (54 mm), tarsometatarsi, phalanges II-1, phalanges II-2, pedal ungual II, phalanges III-1, phalanges III-2, phalanges III-3, pedal unguals III, phalanges IV-1, phalanx IV-2, phalanges IV-3, phalanges IV-4, pedal unguals IV, body feathers, remiges, seven to nine Jinanichthys vertebrae and ribs (Dalsatt et al., 2006)
Diagnosis- (after Chiappe et al., 1999) tarsometatarsus excavated on plantar surface (unknown in C. feducciai).
(after Hou et al., 1999) anterior dentary expanded ventrally (also in C. feducciai).
(proposed) peg-and-socket quadratojugal-quadrate articulation (unknown in other confuciusornithids); double-headed quadrate (unknown in other confuciusornithids); ventral surangular process invading external mandibular fenestra (unknown in C. feducciai); enlarged surangular foramen (also in C. zhengi; unknown in C. feducciai); coracoid foramen absent (unknown in C. feducciai); five pairs of sternal ribs (unknown in C. zhengi); proximoposterior surface of deltopectoral crest concave (unknown in other confuciusornithids); m. humerotricipitalis groove on posterodistal humerus well developed (unknown in C. feducciai); pubic boot absent (unknown in C. dui and C. feducciai).
Comments- Confuciusornis was described based on three poorly preserved specimens and several feathers found in 1993. The holotype was described well by Hou et al. (1995a), though the skull in figure 5b labeled IVPP V109185 may be a typo for the counterpart. While Hou et al. claim the carpometacarpus is unfused, there are no obvious sutures between the semilunate carpal and metacarpals II and III in the excellent photograph in Zhou and Hou (2002). Hou et al. (1995b) erred in stating the postorbital was absent (Zhou, 1999), and incorrectly reconstructed Confuciusornis with a long tail and third manual digit longer than the second. Hou (1997) described the holotype in great detail, probably more than was objectively possible considering the state of the specimen. He also misinterpreted the snout region, mistaking the naris for the antorbital fenestra, the nasal processes of the premaxillae for the nasals, the posterior premaxilla for the maxilla, and part of the maxilla for the prefrontal. One of the paratypes is IVPP V10895, which was similarly described by both Hou et al. (1995a) then in more detail by Hou (1997). Similar to the situation for the holotype, Hou is overzealous in his description, since the large photo in Zhou and Zhang (2006) indicates the entire dorsal ilium and distal pubis are unpreserved, while the hindlimb is fragmented and often only preserved as impressions. The ischium was misinterpreted as complete, although it lacks its distal half, while the pubis was described as unfused to its counterpart, which has been shown to be untrue by specimens which actually preserve the distal pubis. Hou describes a patella which is more likely to be a proximal fibular fragment, and a single distal tarsal which is probably the anteriorly projecting astragalar condyles of the tibiotarsus, but that entire area is fragmented. While measurements for the hallux are provided and metatarsal I illustrated, the entire digit is missing in the specimen. While the tibiotarsofemoral proportions are different from C. dui, they fall into the range of C. feducciai as well as C. sanctus. As both species occur in the same formation, IVPP V10895 cannot be definitively referred to C. sanctus. The paratype distal tibiotarsus and pes IVPP V10919 was made the holotype of Confuciusornis chuonzhous by Hou (1997), but is probably indeterminate within Confuciusornis as discussed under its entry. Finally, six feathers were made paratypes, but these cannot be distinguished from those of other maniraptorans in the formation.
In 1995, four more specimens were discovered by Hou and were initially photographed in Hou et al. (1996). These were fairly complete, but only IVPP V110304 has been subsequently described (Hou, 1997). These specimens included the first pygostyle and pectoral girdle known for Confuciusornis. Oddly, Hou et al. (1996) reported that some specimens lack a pygostyle, but this has not been seen in any described specimen. Hou's description of IVPP V110304 retains his misidentification of snout elements from the holotype, and oddly identifies a septomaxilla (an element unknown in dinosaurs) at the anterior margin of the external naris. This is more likely a vomer or palatine fragment. The sternum was described with anterior and posterior ends reversed.
Peters (1996) and Peters and Ji (1998, 1999) described four specimens from the SMFAv. Guan et al. (1997) described a specimen (BPV 2066), which I believe to be the specimen featured on Digimorph's page (Maisano, 2001). Viohl (1997) described two additional specimens (JM-UKr-1996/15 and 1997/1). Chiappe et al. (1999) published a detailed monograph on Confuciusornis, largely basing it on specimens from the GMV (2130-2133, 2141, 21142, 2146-2155). They noted several areas where the species is polymorphic- ventral tapering of the postorbital; dentary symphysis fusion; two dorsals fused to synsacrum; hypocleidium developed as a swelling; faint keel on sternum; elongate paired retrices. Whether these differences are ontogenetic, sexual, indivual or even taxonomic variation is not known, though generally the specimens with elongate retrices are thought of as males (and labeled as such above). Goernemann (1999) described a privately owned specimen in detail. Hou's (1999) thesis includes a section on Confuciusornis, which was published as Zhou and Farlow (2001) and Zhou and Hou (2002), with figures and data also being used for Martin et al. (1998). Zhou's study was largely based on the specimen IVPP V11552, while Martin et al. mentioned hundreds of specimens were known. Of note is that most of the known IVPP specimens have not been examined to ensure they are C. sanctus instead of C. feducciai or another confuciusornithid, and that many specimens have uncertain provenance, so may be from other members of the Yixian Formation or even the Jiufotang Formation.
Dalsatt et al. (2006) describe the first Confuciusornis specimen from the Jiufotang Formation. It is unlike C. dui in being large and having an anteriorly expanded dentary, large posterior surangular foramen, broad proximal metacarpal I, manual ungual I larger than III, and a comparatively short tibiotarsus. Yet it is more similar to C. dui in lacking a surangular process invading the external mandibular fenestra. The short forelimb, deltopectoral foramen, robust manual digit I, and lack of anterolateral or anteriorly curving posterolateral sternal processes are unlike C. feducciai. Finally, the deep lateral dorsal central fossae, deltopectoral foramen and elongated coracoid are unlike C. zhengi. It it tentatively placed in C. sanctus here, but the presence of a character which is more similar to C. dui and the higher stratigraphic placement suggests it may be a new species.
Confuciusornis suniae- Hou (1997) described Confuciusornis suniae (mistyped Confuciusornis shuzhi in the English summary) based on the nearly complete skeleton IVPP V11308. He distinguished it from C. sanctus based on several characters. The notched anterior median premaxillary margin is present in C. sanctus as well (e.g. GMV-2133). The long dorsal premaxillary process, large external nares and short frontal are present in C. sanctus and were only thought to be absent by Hou due to his misinterpretation of the snout in that species. Hou also states the bulbous frontal with thickened orbital rim is distinct in the text, but the former is present in C. sanctus (e.g. GMV 2133), while the latter may be due to misidentified palpebrals. "Well developed" parietals are too vague to comment on. The cervical vertebrae were said to differ from those of C. sanctus in several characters in the diagnosis (flat and broad centra and neural arches; pleurocoels present; narrow and low neural spines), with others mentioned in the discussion (lateral projection of the transverse processes; thin and expanded centra; prezygapophyses positioned laterally and anteriorly projected). Besides the vague "thin and expanded" centra, the characters are all seen in C. sanctus (Chiappe et al., 1999). Chiappe et al. note cervical pleurocoels are often hard to distinguish, and Hou notes the C. sanctus specimens he studied had poorly preserved cervicals which may have broad centra too. The dorsal vertebrae being "long and thin" is too vague to be useful. "Long and deep grooves" are said to be present in the dorsal central fossae, but their interior morphology is undescribed in C. sanctus. Hou describes three fused "lumbar" vertebrae, but these are clearly the first three sacrals, adding to the four vertebrae described as sacrals to give the standard count of seven for Confuciusornis. Fused sacral neural spines are present in C. sanctus as well (e.g. GMV 2153), whereas the fusion of sacrals to the ilia is not known to be absent in C. sanctus and is ontogenetically variable in any case. "Caudal vertebrae basically fused" is seen in all avebrevicaudans. Chiappe et al. (1999) note the sternal morphology (long and narrow with deep elongate lateral recesses; heart-shaped; without lateral processes) cannot be verified in the specimen, as most of it is covered by other bones. The lateral process may be broken off, while the shape difference is largely due to Hou describing C. sanctus' sternum backwards. Hou et al. notes many supposed appendicular differences in his description, most of which are also present in C. sanctus (ventral tubercle of humerus less prominent; concavity of ectepicondyle of humerus; prominent fibular trochlea on femur; prominent fibular crest on tibia; metatarsus only fused proximally), or within the range of variation of C. sanctus (deltopectoral foramen size; metacarpal III robusticity; limb bone robusticity). A dorsal supracondylar process is reported, but the photo doesn't suggest its presence. The scapulotricipital sulcus on the distal humerus is not known to be absent in C. sanctus. Hou describes the ischium as follows, "The ischium is extremely autapomorphic as there are three processes extending off the main body: The first is relatively short, broad, and forms the posterior wall of the acetabulum. The second process is plate-shaped, extends, and expands obliquely dorsally from the distomedial side of the ilium to the vertebral column, appearing as though it encircles the most posterior portion of the synsacral vertebrae. The third and largest process is one which extends posteriorly to the distal end." The first process is clearly the ilial peduncle, the second is the proximodorsal process, and the third is the ischial shaft itself. These are found in C. sanctus too, but Hou was misled by the incomplete IVPP V10895 he used as the basis for that species' pelvic morphology. Finally, Hou states a prominent fourth trochanter is present, but the swelling is clearly absent in the right femur, and that of the left femur is more likely taphonomic. Hou again identifies a septomaxilla, no doubt erroneously. Ten free caudals are preserved, and the vertebrae making up the pygostyle are distinct, though the neural spines are fused distally. This is distinct from C. sanctus, which has seven free caudals and no differentiation within the pygostyle. Perhaps the specimen is young and the two distalmost free caudals would fuse into the pygostyle when it matured. Hou describes four "short thick rib segments" on the right of the specimen, which may be uncinate processes. He also states that though an olecranal fossa is absent, a small depressed region is observed, whereas Chiappe et al. noted no sign of an olecranal fossa. Although Chiappe et al. state a longitudinal groove is absent on the radius of C. sanctus, Hou reports such a groove in C. suniae that is present proximally. Hou reports five phalanges on manual digit III, the first two very short. This is near certainly caused by a break near the base of phalanx III-2. The ilial process noted over the acetabulum and compared to an antitrochanter is probably the supratrochanteric process. He notes a "low dorsal ridge" on the distal pubis, similar to that described by Paul (2002). A patella is described, though this has not been reported by Chiappe et al., and I am unaware of its presence in any non-ornithurine bird. Hou claims the notched premaxillary tip, subequal length of pedal digits III and IV and enlarged fourth pedal ungual indicate semiaquatic or aquatic habits. I see no reason these characters suggest this, and the first two are present in C. sanctus as well. As reported, the fourth pedal ungual is 20% longer than the third, which is unlike at least some C. sanctus specimens. However, pedal proportions among confuciusornithids are extremely variable, with digit length differing as much as 30% in feet of the same specimen.
The proximal humeral foramen and bowed manual phalanx II-2 confirm this is a Confuciusornis specimen, while the elongate sternal ribs, proximally robust first metacarpal and reduced manual ungual III suggest it is not C. dui. The distally expanded scapula, short forelimb, triangular deltopectoral crest with foramen and robust manual digit I suggests it is not C. feducciai. The dorsal central fossae distinguish it from C. zhengi. The ten free caudals, slightly developed olecranal fossa, radial groove and patella all differ from C. sanctus, but given Hou's record of erroneous interpretation, I'm cautious to accept these as real. I thus agree with the synonymization of Confuciusornis suniae with C. sanctus, as suggested by Chiappe et al. (1999).
Jinzhouornis- Jinzhouornis was named by Hou et al. (2002) in a monograph that has yet to be translated from Chinese. J. yixianensis is the type of the genus, while zhangjiyingia was referred to it. They have largely been ignored in the literature, though Zhou and Zhang (2006) and Zhang et al. (2008) both mention them as valid.
At least some of the characters supposedly diagnosing J. yixianensis are seen in Confuciusornis (eg. snout over 50% of cranial length; tubercle in middle of metatarsal II; small tubercle on metatarsal III) and most others are vague proportions that could also be applied to C. sanctus specimens (eg. long low skull; robust long snout; moderately sized orbit; extremely curved manual unguals; slender humerus). Chiappe et al. (2008) note the low skull is due to crushing and that the manual unguals are not more curved than C. sanctus. Though Hou et al. state the humerus was subequal in length to the scapula, it is clearly broken and was much longer than the scapula if complete. Characters like "braincase small" and "second manual digit not particularly expanded" appear to differ at first glance, but I have a feeling examination of the specimen would show otherwise. I cannot see digit II, but I do see digit III, which is of course more slender. Better photos would be needed to show the cervical vertebrae are shorter than Confuciusornis (Chiappe et al. find they are too incomplete to judge) and Confuciusornis may have had over twelve dorsal vertebrae. The taxon shows the proximal humeral foramen and reduced fourth metatarsal trochlea of Confuciusornis. It differs from C. dui in being large, lacking a proximally tapered metacarpal I and having a larger tibiotarsofemoral ratio for its size. It differs from C. feducciai in having a deltopectoral foramen and from C. zhengi in having deep lateral fossae on a dorsal centrum and a prominent scapular acromion. In 2002, I used some of the above data to provisionally propose J. yixianensis was synonymous with Confuciusornis, but could not then place it more exactly (Mortimer, DML 2002). Chiappe et al. (2008) have now examined the specimen in more detail and synonymized it with C. sanctus, which I agree with.
The diagnosis of Jinzhouornis zhangjiyingia contains characters that could be applied to Confuciusornis sanctus (eg. long large skull; premaxilla extends to posterior part of orbit; infratemporal fenestra well developed; orbit moderate in size; furcular ends widely separated) or are subject to individual variation (humeral shaft robust; furcula slender). Additionally, the premaxillae are said to underlie the frontal, but Chiappe et al. (2008) note the frontal is anteriorly displaced. Finally, the supposed quadratojugal-orbit cannot be confirmed (Chiappe et al., 2008). It shows the robust furcula, bowed manual phalanx II-2 and humeral foramen of Confuciusornis. The first manual ungual is much larger than the third and the anterior dentary is expanded, both unlike C. dui. The short forelimb, deltopectoral foramen and triangular deltopectoral crest are unlike C. feducciai. There also appear to be five pairs of sternal ribs, unlike C. dui and C. feducciai. In 2002, I used much of the above data to provisionally synonymize J. zhangjiyingia with C. sanctus (Mortimer DML, 2002), pending restudy. Chiappe et al. (2008) have recently done that restudy, finding J. zhangjiyingia plots with C. sanctus in limb proportions, and agree it is a junior synonym. Zhou et al. (2003) illustrated the skull and pes as examples of C. sanctus.
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Hou, Zhou, Gu and Zhang, 1995a. Confuciusornis sanctus, a new Late Jurassic sauriurine bird from China. Chinese Science Bulletin. 40(18), 1545-1551.
Hou, Zhou, Martin and Feduccia, 1995b. A beaked bird from the Jurassic of China. Nature. 377, 616-618.
Zhou, 1995. New understanding of the evolution of the limb and girdle elements in early birds - Evidences from Chinese fossils. In Sun and Wang (eds). Sixth Symposium on Mesozoic Terrestrial Ecosystems and Biota, short papers. Beijing: China Ocean Press. 209-214.
Hou, Martin, Zhou and Feduccia, 1996. Early adaptive radiation of birds: evidence from fossils from northeastern China. Science. 274, 1164-1167.
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C. sp. indet. (Chiappe et al., 1999)
Early Aptian, Early Cretaceous
Dawangzhangzi Beds of Yixian Formation, Liaoning, China
Material- two specimens (Chiappe, Ji, Ji and Norell, 1999)
Comments- Chiappe et al. note that two specimens they refer to Confuciusornis sanctus have been found in the Dawangzhangzi Beds, though which they are is uncertain (they may be unknowingly listed above in the main C. sanctus section). Zhou et al. (2003) lists C. sp. as being from that horizon. Zhongornis may be a juvenile representative of Dawangzhangzi Confuciusornis.
References- Chiappe, Ji, Ji and Norell, 1999. Anatomy and systematics of the Confuciusornithidae (Theropoda: Aves) from the Late Mesozoic of Northeastern China. Bulletin of American Museum of Natural History. 242, 1-89.
Zhou, Barrett and Hilton, 2003. An exceptionally preserved Lower Cretaceous ecosystem. Nature. 421, 807-814.
C. sp. indet. (Zhou et al., 2003)
Mid Aptian, Early Cretaceous
Jingangshan Beds of Yixian Formation, Liaoning, China
Comments- Zhou et al. (2003) list Confuciusornis sp. as being found in this member of the Yixian Formation, but none have yet been described. They may be C. sanctus, which seems to be found in both lower and higher sediments.
Reference- Zhou, Barrett and Hilton, 2003. An exceptionally preserved Lower Cretaceous ecosystem. Nature. 421, 807-814.