NOTES ON THE NORTH-AMERICAN TERTIARY MARSUPIALS HERPETOTHERIUM AND PERADECTES
NOTES ON THE NORTH-AMERICAN TERTIARY MARSUPIALS HERPETOTHERIUM AND PERADECTES
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DOI：
10.1139/e83-146
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发表时间：
1983-01-01
影响因子：
1.4
通讯作者：
FOX, RC
中科院分区：
文献类型：
--
作者：
FOX, RC
北美第三纪有袋类的新标本。fugax科普和秀丽隐杆线虫P. elegans Matthew和格兰杰。Herpetotherium是一个有效的属，不同于Peratherium Aymard和Amphiperatherium Filhol，具有平卧的下门牙，其中前2个是扩大的。Herpetotherium的上下齿列为H。fugax一直是一个小didelphine可能食虫的习惯;其臼齿功能集中在一个磨损的冠在近水平面和正交prevallid-postvallum剪切。相比之下，在Peradectes elegans中，下门齿是非特化的; P1拥挤在一个强大的犬齿上，后下前磨牙是清晰的，磨牙三角骨直立，爪骨前后缩短。在近垂直面剪切是一个更重要的牙齿功能比H。fugax。对H. fugax和P. elegans证实了Didelphini和Peradectini部落的认可;这些分支的最后共同祖先可能是晚白垩世。
New specimens of the North American Tertiary didelphid marsupials H. fugax Cope and P. elegans Matthew and Granger are described. Herpetotherium is a valid genus, distinct from Peratherium Aymard and Amphiperatherium Filhol, possessing procumbent lower incisors, the first 2 of which are enlarged. The associated upper and lower dentition of Herpetotherium shows H. fugax to have been a small didelphine of probable insectivorous habits; its molar function centered on a wearing of the crowns in near-horizontal planes and on orthal prevallid-postvallum shear. In Peradectes elegans, by contrast, the lower incisors are unspecialized; P1 is crowded against a robust canine, the posterior lower premolars are trenchant, the molar trigonids are erect and the talonids anteroposteriorly shortened. Shear in near vertical planes was a more important dental function than in H. fugax. The dental anatomy of H. fugax and P. elegans corroborates recognition of the tribes Didelphini and Peradectini; the last common ancestor of these clades was probably Late Cretaceous in age.