禄丰古猿地点的小哺乳动物化石

A PRELIMINARY REPORT ON A MICROMAMMALIAN ASSEMBLAGE FROM THE HOMINOID LOCALITY OF LUFENG, YUNNAN

过去十年,在禄丰古猿地点作了多次的发掘和筛洗,采集到包括食虫类,翼手类,啮齿类和兔形类在内的一千余件标本,使这一小哺乳动物的化石组合从1979年首次报道的6种增加到了38种,成为我国南方新第三纪中期最丰富而有代表性的小哺乳动物群。材料的初步鉴定表明:动物群中有代表我国首次发现的化石科和属;并有相当数量与华北、印巴次大陆和欧洲有密切亲缘关系的类型;其地质时代属最晚中新世保德期,相当于欧洲陆相哺乳动物分期的土洛里期(Turolian)。

In the last decade, many of the fossil vertebrates have been collected at Shihuiba, a small village of Lufeng comity, Yunnan. However, only seven forms of micromammals, Sciuridae indet., Hystrix sp., Brachyrhizomys nagrii, B. tetracharax, B. cf. pilgrimi and Alilepus sp. Castoridae indet, have been reported previously (Qi 1979; Flynn and Qi, 1982; Wu et al, 1981). Actually, since the first account based on the material processed from 1975 to 1976, additional material of small mammals has been obtained, particularly in the last field season of 1983 when the wet-sieving techniques were carried out at that locality. Up to now, at least 32 taxa of micromammals can be added to the list of the fauna (see P.22, Table 1). The collection is of particular significance as it represents the few Neogene faunas of South China, containing not only the most abundant and diverse small and large mammals associated with hominoids, but also many elements new for the fossil record in China or Asia. The purpose of this paper is to report all the micro-mammalian fossils excavated and washed at this locality during the past ten years. Detailed descriptions of these taxa will be given in the next few years. The specimens reported in this paper were recovered from the deposits of section D (see Qi, 1985) by traditional excavation in the field seasons from 1975 to 1983 and wet-screening of about 10 tons of sediments from layers 1, 2, 5 and 6 in 1983. Some 1175 specimens have so far been identified, of which more than 1000 were sorted from two third of wet-screened concentrate. About 150 kg of this residue washed remain to be picked. In the material, insectivores are aboundantly represented. Twenty isolated teeth, including incisors and premolars, are identified as tupaiid and all are probably assignable to one species. The tooth pattern of this form is similar to that of the living tupaiid of South Asia, and the lower molar is comparable in size and morphology to the Siwalik specimen YGSP 8090 (Jacobs, 1982, p. 212). This is the first fossil record of it for China. Although there has been much discussion on the taxonomic status of this animal in the literature, it is temporarily accepted in this paper that tree shrew is placed in Insectivora. Ninety eight specimens, including 4 dentary fragments represent two genera of erinaceids, Galerix and Lanthanotherium. In size and morphology the Galerix (21 specimens) is close to the Siwalik G. ruttandae, but metaconid on P4 is rather weak. In general crown morphology, the specimens of the smaller hairy hedge- hog are clearly comparable both the Neogene Lanthanotherium of Europe and North America and to the extant Hylomys of oriental province. It is necessary to make a through investigation of the relationship to the living genus or the fossil one. Moles are also common (87 specimens), but only one taxon is identified. In its dental formula, morphology of humerus and in its enlarged I1 and reduced first premolar (P1 or P2), it differs from Tanshuella of Ertemte and other known Chinese moles, but can be referred to Scalopini. There are 70 soricid specimens in the collection, assigned to 5 forms. A species of Herterosoricinae is represented by 3 mandible fragments and 8 teeth. The discovery of herterosoricine in this fauna is of the first record in East Asia. The Lufeng form seems to be closely related either to the Dinosorex or Heterosorex of Europe. Anourosorex is relatively common in the shrew material (3 dentary fragments and 34 teeth). These specimens differ from those of North China and Europe in more reduced M3 and may represent a new species. A species of Blarinella (11 specimens) is similar morphologically to B. kormosi, but smaller in size. Three teeth may be assigned to Crocidura, while another eight are of a soricine, but not identifiable below the subfamily level. Three families of Chiroptera, Pteropidae (2 teeth), Hipposideridae (3 teeth) and Vespertilionidae (28 specimens) can be recognized in this fauna, of these Pteropidae previously were unreported from the Chinese fossil sediments. Th