作者:Som Nath KUNDAL Gyan BHADUR Sandeep KUMAR
摘要:报道和描述了一件平额象左侧M3化石。新材料产自Nangal村附近火山灰层之下的泥岩层,该火山灰是出露于查谟-克什米尔桑巴地区Barakhetar上西瓦立克亚群Nagrota组中年龄为2.48 Ma的火山灰层的延伸。根据齿板数,臼齿长和宽,齿冠长、宽和高,釉质和齿质厚度,齿板长和宽,齿脊频率,冠高指数以及白垩质厚度等齿冠形态参数,暂时将之归为Elephas cf. E. planifrons。新材料的发现将该种的分布上限从2.6 Ma提高到2.48 Ma
关键词:印度查谟,上西瓦立克亚群,Nagrota组,象类
卷期:第55卷,第1期
Elephas cf. E. planifrons (Elephantidae, Mammalia) from Upper Siwalik Subgroup of Samba district, Jammu and Kashmir, India
Som Nath KUNDAL, Gyan BHADUR, Sandeep KUMAR
Abstract One specimen of Elephas cf. E. planifrons is reported and described here in the present paper. The specimen was recovered from the mudstone horizon underlying the volcanic ash bed exposed near the Nangal village, which is the extension of geochronological dated (2.48 Ma) volcanic ash beds exposed at Barakhetar in the Nagrota Formation of Upper Siwalik Subgroup of Samba district, Jammu and Kashmir, India. Based on the crown morphological parameters (plate numbers, molars length and width, crown length, width and height, enamel thickness, dentine thickness, length and width of plates, lamellar frequency, hypsodonty index and cement thickness), the specimen has been identified and is tentatively referred to Elephas cf.E. planifrons (LM3). The recovery of this specimen is of great significance as it extends its upper limit of range zone from 3.6–2.6 to 3.6–2.48 Ma.
Key words Jammu, India; Nagrota Formation, Upper Siwalik Subgroup; Elephas