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Changchengornis Ji Q., Chiappe & Ji S., 1999

Changchengornis Ji Q., Chiappe & Ji S., 1999 (Journal Vertebr. Paleontol. 19 (1), 15 March: 1 NcZ) "Great Wall bird"
chahng-chuhng-OR-nis (Chin. Chang Cheng (Great Wall) + Gr. ornis "bird")* (m) referring to the Great Wall of China (Chang Cheng), famous manmade structure erected south of the northeastern region of China in which the fossil was found (Liaoning Province, Sihetun-Jianshangou area); for a blue jay-sized, toothless confuciusornithid bird, differing from Confuciusornis in having a strongly curved beak and a lower jaw that is very deep at the back and much shorter than the skull; differing also in proportions of the metacarpals and hallux, and in the lack of an opening (foramen) on the deltopectoral muscle crest on the humerus. The large sternum is flat without a keel, overlapping the first two rows of a set of gastralia. The type specimen (GMV2129-a/b) in the National Geological Museum of China (Beijing) consists of two counterslabs of a nearly complete specimen preserving most of the plumage as a carbonized halo around the fossil bones. There is no tailfan, but the tail bears two long ribbon-like feathers, a feature also preserved in some specimens of Confuciusornis and possibly associated with sexual dimorphism (indicating males?), though it might have been found in both sexes and only missing in some Confuciusornis specimens because of immaturity or moulting.
The foot structure in Changchengornis indicates well-developed perching ability. Hou, Martin and Zhou (1996) have suggested that Confuciusornis (and presumably the closely related new genus) might have been specialized for climbing trees because of a proposed upright, squirrel-like posture and forelimbs with long-clawed digits. However, other researchers have disputed such an unusual posture (unlike any known bird or dinosaur), as well as the idea that the large curved digits on the wings were designed for climbing.
Type Species: Changchengornis hengdaoziensis [HUHNG-dowd-zuh-EN-sis] Ji Q., Chiappe, Ji S., 1999: for the Hengdaozi stratigraphic horizon (Early Cretaceous?) of the Chaomidianzi Formation. Metornithes Confusiusornithidae Late Jurassic-Early Cretaceous China [entry added 4-99]

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Type species: Changchengornis hengdaoziensis Ji Q., Chiappe & Ji S., 1999


Описание Changchengornis

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