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''Chaoyangopterus'' is a genus of azhdarchoid pterodactyloid pterosaur known from a partial skeleton found in Liaoning, China. It was found in rocks of the Aptian-age Lower Cretaceous Jiufotang Formation of Dapingfang, Chaoyang. The genus was named and described in 2003 by Wang Xiao-Lin and Zhou Zhong-He. The type species is ''Chaoyangopterus zhangi''. The genus name is derived from Chaoyang and a Latinised Greek ''pteron'', "wing". The specific name honours journalist Zhang Wanlian for his efforts in protecting fossil sites. The genus is based on holotype IVPP V13397, which includes the front of the skull, the lower jaws, the neck vertebrae, the shoulder and pelvic girdles, and the limbs. The skull is about 270 millimeters long (10.6 inches) and toothless, and its wingspan is estimated to have been around 1.85 meters (6.07 feet). Wang and Zhou concluded that it compared most closely to ''Nyctosaurus'' and classified it as a nyctosaurid, although they found that its shin was proportionally longer compared to the femur and humerus in ''Chaoyangopterus'', that their animal had relatively shorter wings and longer legs than ''Nyctosaurus'', and that it still had four fingers. The classification of ''Chaoyangopterus'' has since become unsettled, with subsequent reviewers disagreeing with the nyctosaurid assessment. David Unwin, in a popular work, included it without comment with the tapejarid family of azhdarchoid pterosaurs, known for their large head crests. A detailed phylogenetic analysis of Liaoning pterosaurs published by Junchang Lü and Qiang Ji in 2006 found it instead to be a basal azhdarchoid of no particular familial affiliation. However, subsequent analysis by Lu and Unwin found that within the Azhdarchoidea it formed a clade with several other forms such as ''Jidapterus'' and ''Shenzhoupterus'', which they named Chaoyangopteridae.〔Lü, J., Unwin, D.M., Xu, L., and Zhang, X. (2008). "A new azhdarchoid pterosaur from the Lower Cretaceous of China and its implications for pterosaur phylogeny and evolution." ''Naturwissenschaften'', 95: 891–897〕 Wang however, in 2006 stated that ''Chaoyangopterus'' was a member of the Pteranodontidae and that ''Jidapterus'', ''Eoazhdarcho'' and ''Eopteranodon'' are subjective junior synonyms of the former.〔Wang, X. and Zhou, Z. (2006), "Pterosaur assemblages of the Jehol Biota and their implication for the Early Cretaceous pterosaur radiation", ''Geological Journal'' 41: 405–418〕 ==Paleobiology== ''Chaoyangopterus'' is known to have been a toothless pterosaur and was assumed by Wang to have been a piscivore or fish-eater, but other relevant details of its paleobiology will have to await a more detailed description. Chaoyangopterids in general are now thought to have been similar to azhdarchid pterosaurs, implying that they were probably crane-like terrestrial omnivores and opportunistic carnivores.〔http://pterosaur.net/species.php〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Chaoyangopterus」の詳細全文を読む スポンサード リンク
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