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Gwawinapterus
''Gwawinapterus'' is a genus of Mesozoic animal known from a single fossil specimen, representing the single species ''Gwawinapterus beardi'', from the late Cretaceous period of British Columbia, Canada. While initially described as a very late-surviving member of the pterosaur (flying reptile) group Istiodactylidae, further examination has cast doubt on the identification of the specimen as a pterosaur, and research published in 2012 identified the remains as having come from a saurodontid fish.
==Description==
''Gwawinapterus beardi'' is known from a single fossil specimen, consisting only of the front half of a skull (upper and lower jaws). The tip of the snout is rounded and deep with a height of about . The tip is about from the front edge of the largest skull opening, or ''fenestra''. Below this opening the upper jaw is about tall. The jaw was originally suggested to be a sutureless fusion of the premaxilla and maxilla of a reptile. Each upper jaw holds at least 26 teeth, eleven or twelve of them below the fenestra; the front of the tooth row has not been preserved and the fossil is broken at its end. The teeth are closely packed. The tooth crowns are small, tall and wide, flattened, and triangular with slightly curved edges. The edges are not serrated, but rounded. The teeth are very straight, showing no curvature to either the back or the middle. The more narrow single tooth roots are relatively long, about , for a total tooth length of about .〔
The describers have identified two unique derived features (autapomorphies): a number of more than 25 teeth in the upper jaw and a tooth root more than twice as long as the crown.〔
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
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