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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