内蒙古上渐新统中Yindirtemys(啮齿目,梳趾鼠科)的发现

DISCOVERY OF YINDIRTEMYS (CTENODACTYLIDAE, RODENTIA, MAMMALIA) FROM LATE OLIGOCENE OF NEI MONGOL, CHINA

在内蒙古上渐新统伊克布拉格组中发现的 Yindirtemys 的新材料证明,Yindirtemys woodi 是 Tataromys grangeri 的晚出的同物异名,但 Tataromys grangeri 的特点与典型的 Tataromys 的区别很大,而 Yindirtemys 属仍是有效的.因此,这个种应从 Tataromys 属中排除,而归人 Yindirtemys 属.

Yindirtemys is a more advanced ctenodactylid. The only species known, Y. woodi, was described by Bohlin (1946) on the basis of a M3/(T. b. 577) from Taben Buluk, Gansu (=Kansu) Province, China. At the same time, based on some other specimens (without M3/) from the same level of the same locality, Bohlin described a new, small-sized species of Tataromys: Tataromys grangeri. Unfortunately, however, the two species did not share any specimen which could be directly compared with each other. Since then no more material of Yindirtemys has been reported. The nature of Yindirtemys and its relationships with other ctenodactylids have been obscure. Recently, studying on the ctenodactylids from Nei Mongol, the author found some specimens belonging to Yindirtemys. It is more interesting that there is a left fragment of maxilla with M2/-3/ which is similar to Tataromys grangeri in the features of M2/, but to Yindirtemys Woodi in M3/. It reveals that Yindirtemys woodi is a junior synonym of Tataromys grangeri. However, because it differs from the typical Tataromys, Tataromys grangeri is to be relocated from Tatoromys to Yindirtemys.