辽宁下白垩统阜新组真兽类哺乳动物新带氏远藤兽(Endotherium niinomii Shikama,1947)再研究（英文）

Reappraisal of Endotherium niinomii Shikama, 1947, a eutherian mammal from the Lower Cretaceous Fuxin Formation, Fuxin-Jinzhou Basin, Liaoning, China

根据正型标本的印痕和翻制的模型,重新研究了产于辽宁阜新新邱阜新组的早白垩世真兽类哺乳动物新带氏远藤兽(Endotherium niinomii Shikama,1947)。对照Shikama(1947)的原始描述,将E.niinomii的主要特征归纳为:下臼齿从m1到m3逐渐变小;下三角座和下跟座的高差不是很大;下臼齿的齿尖钝;下原尖比下前尖和下后尖大,并且下前尖和下后尖高度相近;可能有5个前臼齿,并且p3不明显变小。这些特征组合足以将该属与其他的白垩纪真兽类相区别,因此认为Endotherium niinomii是一个有效种。

Reinvestigation of the Early Cretaceous eutherian mammal Endotherium niinomii Shikama,1947,based on the impressions of the type specimen,casts made from the impressions,and the original description,indicates that E.niinomii is characterized by the following characters:decrease in size from the m1 to the m3;a moderate height difference between the trigonid and talonid of lower molars;blunt lower molar cusps;the protoconid being the largest among the trigonid cusps;the paraconid being as tall as the metaconid;the p3 not being obviously reduced;and possible possession of five lower premolars.These characteristics clearly distinguish E.niinomii from other known Cretaceous eutherians,and support its taxonomic identity as a valid taxon.