甘肃兰州盆地中中新世泉头沟动物群的食虫类、跳鼠类和兔形类

INSECTIVORE, DIPODOIDEAN AND LAGOMORPH FROM THE MIDDLE MIOCENE QUANTOUGOU FAUNA OF LANZHOU, GANSU

记述了甘肃兰州永登下街泉头沟发现的5种小哺乳动物化石，其中包括3个首次在这一经典地点发现的种。化石组合的分析表明，泉头沟动物群的时代与内蒙古中中新世通古尔动物群接近，并有一个与通古尔动物群相似、指示温带干旱、半干旱丛林-草原的古环境。

Quantougou of Xianshuihe (Hsienshuho), Yongdeng (Pingfang Hsien), Gansu (Kansu) is a Neogene mammalian locality known since 1927. The Quantougou microfauna, first described by Young (1927) and revised by Schaub (1930, 1934), yielded four species, Plesiodipus leei Young 1927, Paracricetulus schaubi Young 1927, Heterosminthus orientalis Schaub 1930 and Protalactaga grabaui Young 1927. All these taxa, however, were represented by scarce material, and their intraspecific variation was unknown. It was highly desirable not only to get additional material from the type area, but also to increase the known taxonomic diversity for this important Miocene locality in northwestern China. The material which forms the basis of this study was collected mainly in the field season of 1991 by means of screen-washing. Six families of small mammals, Erinaceidae, Gliridae, Zapodidae, Dipodidae, Cricetidae and Ochotonidae, represented by 898 fragmentary jaws and teeth were recovered from about 150 kg of sediments of the upper part of the Xianshuihe Formation. Although the collection is not so diverse taxonomically, the quantity of the specimens affords an opportunity to study the limits of individual variation of the type species, which are common in the Miocene deposits of North China. This paper deals in detail with the insectivore, dipodoidean and lagomorph. Description of the glirids and cricetids will be given in another forthcoming paper. For the geological background of the locality, the reader is referred to the paper “Recent Advances in Study of the Xianshuihe formation in Lanzhou Basin” by Qiu Zhanxiang and others (1997).