山东早始新世五图组的一种古有蹄类Olbitherium millenariusumgen.et sp .nov.(哺乳动物纲,“伪齿兽集目”)

OLBITHERIUM MILLENARIUSUM,A NEW PERISSODACTYL-LIKE ARCHAIC UNGULATE (MAMMALIA) FROM THE EARLY EOCENE WUTU FORMATION,SHANDONG

记述了在山东省五图盆地下始新统发现的一种“伪齿兽集目”化石 :千禧福兽 (Olbither iummillenariusumgen.etsp .nov.)。千禧福兽其颊齿形态基本上与原始奇蹄类相似 ,同时也具有伪齿兽类的一些特征 ,如m1～ 2下次尖没有与下内尖直接连接的下次脊。千禧福兽的M3次尖具前、后棱 ,这一点似与原始的蹄兔Seggeurius相似。因此 ,新种在目一级的归类有困难 ,暂置于McKenna ( 1 975 )创立的“伪齿兽集目”(“MirorderPhenacodonta”)。千禧福兽的发现进一步证明了奇蹄类可能起源于亚洲和北非类似伪齿兽类 (phenacodontids)的古有蹄类 ,福兽仅是类似伪齿兽类的古新世古有蹄类向奇蹄类进化过程中的一叉支的代表。

A unique mammal was found from the Early Eocene of the Wutu Basin, Shandong Province, China. The upper molars of the species are similar to those of early perissodactyls in general morphology, but the m1～2 are much like those of phenacodontids in having an incomplete hypolophids, and the M3 has a hypocone with prehypocrista and posthypocrista, which is similar to that of primitive hyraxes. It is difficult to assign the new species to the order Perissodactyla or other definite orders. It seems advisable to refer the new species to “Mirorder Phenacodonta”, including Condylarthra, Perissodactyla and Hyracoidea ( sensu McKenna, 1975).