作者：李 茜

摘要：为完善内蒙古二连盆地古近纪生物年代框架和明晰该地区啮齿类化石多样性，报道了二连盆地额尔登敖包剖面新发现的啮齿类化石材料，包括上白层中的查干鼠类(Cyclomylus lohensis, Coelodontomys asiaticus), 中红层和下红层中的圆柱齿鼠类(Gobiocylindrodon sp., Proardynomys sp.和 Cylindrodontidae gen. et sp. indet.), 及下白层中的梳趾鼠类(Yuomys sp.)。上白层中发现的查干鼠类证实了上白层时代为早渐新世。基于额尔登敖包上白层与脑木根敖包顶部岩层岩性相似，动物群中有部分相同的组成，进一步确认二者应当属于同一个组。额尔登敖包剖面圆柱齿鼠类化石以不同的组合出现在不同的层位中，这些标本表明始新世时在亚洲圆柱齿鼠类已经有较高的分异度，同时该类群在亚洲可能有相对连续的演化序列。

关键词：内蒙古，额尔登敖包，始新世-渐新世，查干鼠类，圆柱齿鼠类，梳趾鼠类
卷期：第59卷，第1期

Additional tsaganomyid, cylindrodontid and ctenodactyloid rodent materials from the Erden Obo section, Erlian Basin (Nei Mongol, China)

LI Qian

Abstract To improve the Paleogene biochronological framework of the Erlian Basin, Nei Mongol and clarify the diversity of fossil rodents in this region, new tsaganomyids (Cyclomylus lohensis, Coelodontomys asiaticus) from the “Upper White” beds, cylindrodontids (Gobiocylindrodon sp., Proardynomys sp., and Cylindrodontidae gen. et sp. indet.) from the “Middle Red” and “Lower Red” beds, and ctenodactyloids (Yuomys sp.) from the “Lower White” beds of the Erden Obo section are reported. The appearance of C. lohensis and Co. asiaticus from the Erden Obo section confirms that the age of the “Upper White” beds is Early Oligocene. The “Upper White” beds of the Erden Obo section and the top bed of the Nom Khong Obo are confirmed to belong to the same formation by both lithofacies and mammalian fossils. The different kinds of cylindrodontids found from the different horizons of the Erden Obo section show that the cylindrodontids had a high diversity and a relative continuous evolution in Eocene Asia.

Key words Nei Mongol, Erden Obo, Eocene-Oligocene, tsaganomyid, cylindrodontid, ctenodactyloid