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Maniraptoriformes is a clade of dinosaurs with pennaceous feathers and wings that contains ornithomimosaurs and maniraptors. This group was named by Thomas Holtz, who defined it as "the most recent common ancestor of ''Ornithomimus'' and birds, and all descendants of that common ancestor." == Fossil evidence == Many fossils have been discovered in recent years, particularly in China. Many of the feathered dinosaurs belong to this clade. In particular, a fossil of the Alvarezsauridae ''Shuvuuia'' has a version of keratin consistent with that of avian feathers. Many nearly complete fossil maniraptoriforms are known from the late Jurassic. ''Archaeopteryx'' is known from Bavaria at 155-150 Ma. ''Ornitholestes'', the troodontid WDC DML 110, ''Coelurus fragilis'' and ''Tanycolagreus topwilsoni'' are all known from the Morrison Formation in Wyoming at about 150 Ma. The Daohugou biota, including ''Anchiornis'' and ''Epidexipteryx'', is the earliest record of maniraptoriformes, dating to about 160 Ma. One possible maniraptoriform, ''Eshanosaurus'', lived even earlier, during the Early Jurassic, though its identification is controversial. The wide range of fossils in the early Cretaceous and morphological evidence suggests that the main branches of maniraptoriform differentiation were separate before the end of the Jurassic. Until recently, the relatives of ''Tyrannosaurus'' were thought to be maniraptoriforms,〔Benton, Michael J. (2004) (Vertebrate Palaentology ). 3rd ed. Wiley. ISBN 978-0-632-05637-8〕 but this now seems unlikely.〔Weishampel, David B., Dodson, Peter, and Osmólska, Halszka (2004) ''The Dinosauria''. University of California Press. ISBN 0-520-25408-2〕 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「Maniraptoriformes」の詳細全文を読む スポンサード リンク
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