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''Epidexipteryx'' is a genus of small paravian dinosaurs, known from one fossil specimen in the collection of the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing. ''Epidexipteryx'' represents the earliest known example of ornamental feathers in the fossil record. The type specimen is catalog number IVPP V 15471. It has been reported to be a maniraptoran dinosaur from the Middle Jurassic or Upper Jurassic age Daohugou Beds of Inner Mongolia, China (about 160 or 168 mya). The specific name, ''Epidexipteryx hui'' ("Hu's display feather"), and its Chinese name Hushi Yaolong ("Hu Yaoming's dragon") were coined in memory of paleomammologist Hu Yaoming. ==Description== ''E. hui'' is known from a well preserved partial skeleton that includes four long feathers on the tail, composed of a central rachis and vanes. However, unlike in modern-style rectrices (tail feathers), the vanes were not branched into individual filaments but made up of a single ribbon-like sheet. ''Epidexipteryx'' also preserved a covering of simpler body feathers, composed of parallel barbs as in more primitive feathered dinosaurs. However, the body feathers of ''Epidexipteryx'' are unique in that some appear to arise from a "membranous structure"〔 at the base of each feather. It has been suggested that this may represent a stage in the evolution of the feather.〔http://scienceblogs.com/tetrapodzoology/2008/10/epidexipteryx_at_last.php〕 In all, the skeleton of ''Epidexipteryx hui'' measures 25 centimeters (10 inches) in length (44.5 cm or 17.5 in including the incomplete tail feathers),〔Zhang, F., Zhou, Z., Xu, X., Wang, X. and Sullivan, C. (2008). "A bizarre Jurassic maniraptoran from China with elongate ribbon-like feathers", Supplementary Information. ''Nature'', 455: 46pp. PMID 18948955〕 and the authors estimated a weight of 164 grams, smaller than most other basal avialans.〔 The skull of ''Epidexipteryx'' is also unique in a number of features, and bears an overall similarity to the skull of ''Sapeornis'', oviraptorosaurs and, to a lesser extent, therizinosauroids. It had teeth only in the front of the jaws, with unusually long front teeth angled forward, a feature only seen in ''Masiakasaurus'' among other theropods. The rest of the skeleton bore an overall similarity to the possibly closely related ''Scansoriopteryx'', including a hip configuration unusual among other dinosaurs: the pubis was shorter than the ischium, and the ischium itself was expanded towards the tip. The tail of ''Epidexipteryx'' also bore unusual vertebrae towards the tip which resembled the feather-anchoring pygostyle of modern birds and some oviraptorosaurs.〔 ''Epidexipteryx'' appears to have lacked remiges (wing feathers), though based on the related ''Yi'', it may have possessed some sort of membrane wing to allow gliding.〔Cau, A (2012), (ritorno del paraviano pterosauro-mimo? ), Theropoda, July 2012〕〔 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「Epidexipteryx」の詳細全文を読む スポンサード リンク
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