| 翻訳と辞書 |
Eozostrodon
''Eozostrodon'' is an extinct Morganucodont mammaliform. It lived during the Rhaetian stage of the late Triassic into the early Jurassic. ''Eozostrodon'' is known from disarticulated bones in Wales and Southwest England and estimated to have been less than in head-body length, slightly smaller than the similar-proportioned ''Megazostrodon''.〔
''Eozostrodon'' was described on the basis of two teeth discovered in a quarry near Frome in Somerset, England, each originally assigned to separate species ''E. parvus'' and ''E. problematicus''. The latter was synonymized in 1971.〔 The identity of and status of ''Eozostrodon'' is controversial. Kühne considered ''Eozostrodon'' to be "one and the same" with ''Morganucodon'' which he described, albeit after the published description of ''Eozostrodon'', claiming "...for a number of good reasons ''Morganucodon'' ought to be used, the name of ''Eozostrodon'' being used for sentimental reasons only or because of ignorance." Jenkins and Crompton in 1979 argued ''Morganucodon'' was a subjective synonym of ''Eozostrodon'',〔F. A. Jenkins and A. W. Crompton. 1979. "Triconodonta. In J. A. Lillegraven, Z. Kielan-Jaworowska, W. A. Clemens (eds.), ''Mesozoic Mammals: the First Two-Thirds of Mammalian History'' 74-90. (Summary )〕 yet Clemens (1979) argued for the distinction. A more recent publication again distinguished the two, noting that ''Eozostrodon'' differs from ''M. watsoni'' in relative size and shape of premolar structures.〔Z. Kielan-Jaworowska, R. L. Cifelli, and Z.-X. Luo. 2004. ''Mammals from the age of dinosaurs: Origins, evolution, and structure.'' Columbia University Press, New York 1-630.〕
Its teeth were typically mammalian, being differentiated into molars and premolars with triangular cusps.
==References==
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「Eozostrodon」の詳細全文を読む
スポンサード リンク
| 翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|