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''Coloborhynchus'' is a genus in the pterosaur family Ornithocheiridae, and is known from the Lower Cretaceous of England (Albian age, 98 million years ago), and possibly the Aptian age (112-99 million years ago) of Brazil and Texas, depending on which species are included. ==Description== The type specimen of ''Coloborhynchus'' is known only from a partial upper jaw. Therefore, according to Rodrigues and Kellner's 2008 re-evaluation on ''Coloborhynchus clavirostris'', it can only be differentiated from its relatives based on its unique combination of tooth socket positions. In ''Coloborhynchus'', the two front teeth pointed forward and were higher on the jaw than the other teeth, while the next three pairs of teeth pointed to the sides. The final two (preserved) pairs of teeth pointed downward. Finally, a unique oval depression was located below the first pair of teeth.〔Rodrigues, T. and Kellner, A.W.A. (2008). "Review of the pterodactyloid pterosaur ''Colobrohynchus''." Pp. 219–228 in: Hone, D.W.E. and Buffetaut, E. (eds), ''Flugsaurier: pterosaur papers in honour of Peter Wellnhofer. Zitteliana B'', 28.〕 Like the related ''Anhanguera'' and ''Uktenadactylus'', the tip of the snout flared out into a wider rosette, in contrast to the narrow posterior jaws. However, whereas the rosettes of species typically assigned to ''Anhanguera'' were rounded and spoon-shaped, those of ''coloborhynchus'' were robust and box-shaped. Also like its close relatives, ''Coloborhynchus'' had a keel-shaped crest on the front of its jaws, though it was broad and thinned from base to top, rather than the uniformly thin crests of its relatives. This kind of thickened crest is also seen in ''Siroccopteryx moroccensis'', which may be its closest relative or a member of the same genus. It also had a straight, rather than curved, front margin, unlike its relatives, and begins at the tip of the snout, rather than further back as in other species.〔 A second specimen showing all of these same unique features was reported to Brazilian paleontologist Alexander Kellner by Darren Naish in 2007, and likely represents a second specimen of ''C. clavirostris'', though it has not yet been described.〔 The possible species ''Coloborhynchus capito'' represents the largest known ornithocheirid, and indeed the largest toothed pterosaur known. A referred specimen from the Cambridge Greensand of England described in 2011 consists of a very large upper jaw tip which displays the tooth characteristics that distinguish ''C. capito'' from other species. The jaw tip is nearly 10 cm tall and 5.6 cm wide, with teeth up to 1.3 cm in base diameter. If the proportions of this specimen were consistent with other known species of ''Coloborhycnhus'', the total skull length could have been up to 75 cm, leading to an estimated wingspan of .〔Martill, D.M. and Unwin, D.M. (2011). "The world's largest toothed pterosaur, NHMUK R481, an incomplete rostrum of ''Coloborhynchus capito'' (Seeley 1870) from the Cambridge Greensand of England." ''Cretaceous Research'', (advance online publication). 〕 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「Coloborhynchus」の詳細全文を読む スポンサード リンク
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