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近年,作者在安徽淮南大居山陆续发现了数量很多的上新五褶兔化石,其中包括保存较完整的数十个头骨及上百个下颌骨,均产自新洞、无名洞及铁四局洞穴、裂隙堆积,分别记述为大居山上新五褶兔Pliopentalagus dajushanensis sp.nov.和安徽上新五褶兔Pl.anhuiensis sp.nov.两新种。淮南地区的晚新生代洞穴和裂隙堆积十分发育,其中常含有丰富的脊椎动物化石,而且在时、空分布上有一定的规律。区内洞穴和裂隙堆积垂直分布至少有6个水平层,最高的第6层海拔高度为160 m(如大居山老洞),第5层(如大居山新洞、无名洞)及第4层(如大居山铁四局洞穴)的海拔高度分别为130 m和90 m,属于新近纪,常含有丰富的上新五褶兔化石;第3层为第四纪早期(如大居山西裂隙),未见上新五褶兔,代之出现丝绸兔(Sericolagus sp.),第2层为中更新世(如大顶山西裂隙),出现野兔(Lepus sp.)。迄今为止,安徽淮南地区共发现了3种上新五褶兔化石,即淮南上新五褶兔Pl.huainanensis (金昌柱,2004)、大居山上新五褶兔Pl.dajushanensis sp.nov.及安徽上新五褶兔Pl. anhuiensis sp.nov.,至少涉及了3个不同地质时期的动物群:一为Pl.huainanensis,Kowalskia neimengensis,Adcrocuta eximia等代表的老洞晚中新世动物群,二为Pl.dajushanensis sp.nov.和Promimomys asiaticus等代表的新洞早上新世动物群,三为Pl.anhuiensis sp.nov.和Kowalskia yinanensis所代表的晚上新世动物群。淮南地区发现的3种上新五褶兔地史分布较连续,演化特征明显,它们构成上新五褶兔连续的进化系列。从晚中新世至晚上新世,淮南大居山上新五褶兔体型从小变大;p3较原始的釉岛状后内褶沟逐渐向舌侧开放(晚中新世种Pl. huainanensis的后内褶沟均为釉岛状,早上新世种Pl.dajushanensis为83.9%,晚上新世种Pl. anhuiensis为33.3%);p4-m2的前外褶沟逐渐退化,其下跟座舌侧的釉质层越来越变细。依性状分析,安徽发现的3种上新五褶兔化石与日本琉球奄美黑兔(Pentalagus furnessi)具有密切的亲缘关系,但从日本奄美黑兔的p4-m2完全缺失前外褶沟、颊齿褶沟釉质层的褶曲异常复杂等衍生性状看,上新五褶兔和奄美黑兔的系统演化关系较为复杂,尚有待发现更多早更新世的材料进一步探讨。
In recent years, the authors discovered a large number of the upper Pleistocene pentaphyllum fossils in Dahuju Mountain, Huainan, Anhui Province. These include preserved dozens of skulls and hundreds of mandibles, all of which originate from new caves, Bureau caverns and crevices accumulate, which are respectively described as Pliopentalagus dajushanensis sp. Nov., And new species of Pl.anhuiensis sp. Nov. The late Cenozoic caves and fissures in Huainan area are well developed. They often contain abundant vertebrate fossils, and have certain regularities in time and space distribution. There are at least 6 horizontal layers in the vertical distribution of caves and fissures in the area, with the highest elevation of the 6th layer being 160 m (such as the Dagushan Old Cave), the fifth layer (such as the Dadu Mountain Cave and the Anonymous Cave) The 4th floor (such as the Daciushan Iron Cave) has an altitude of 130 m and 90 m, respectively, and belongs to the Neogene, which is often rich in Xinpengqincao fossils. The third layer is an early Quaternary period Shanxi fissure). No new pentagrams rabbit was found. Sericolagus sp. Was replaced by silk sericola sp., While the second layer was mid-Pleistocene (such as Shanxi Dading Shanxi Fissure). Lepus sp. Appeared. To date, three species of newly formed five-fold-pleated fossils have been discovered in Huainan, Anhui Province, namely Pl.huainanensis (Jinchangzhu, 2004), the new pentapod rabbit Pl.dajushanensis sp.nov. At present, there are at least three fauna groups in different geologic periods: one is the Late Palaeo-Miocene fauna represented by Pl.huainanensis, Kowalskia neimengensis, Adcrocuta eximia, The New Cave Early Pliocene represented by Pl.dajushanensis sp.nov. And Promimomys asiaticus, and the third Pheasant fauna represented by Pl.anhuiensis sp. Nov. And Kowalskia yinanensis. The distribution patterns of the three new Shangqiu five-fold rabbits found in Huainan area are more continuous and evolve distinctly. They constitute the continuous evolutionary series of the newly formed pentagrams. From late Miocene to late Pliocene, the body size of new pentagrams on Dahuju Mountain in Huainan increased from small to large; p3 gradually opened to the lingual side compared with the original glacial island-shaped posterior fold (Late Neocene Pl. Huainanensis later The inner fold was of the glaze island shape, 83.9% of the new-breed Pl. Dajushanensis in the morning and 33.3% of the new-breed Pl. Anhuiensis in the evening). The anterior furrow of p4-m2 gradually degenerated, Enamel layer more and more thinner. According to the trait analysis, the three newly discovered pentagonal fossilized fossils found in Anhui Province are closely related to Pentalagus furnessi. However, the p4-m2 of Japanese Amami black rabbits completely lacked anterior outer furrows, Tuck furrow enamel layer of abnormal folding and other derivatives derived from the see, the new five-fold rabbit and Amami black rabbit phylogenetic relationship is more complicated, yet to be found in more early Pleistocene material to further explore.