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记述了安徽潜山盆地古新世裂齿目一新属种 ,命名为潜水本爱兽 (Benaiusqianshuiensisgen .etsp .nov .)。标本产于望虎墩组下段底部 ,为一带犬齿和完整颊齿列的左下颌骨。新种的主要特点是 :个体较小 ,下齿列齿式 2 + ?·1·4·3,i2略有增大 ,p1存在但退化成单根且侧扁 ,p3无下后尖 ,p4次臼齿化且无下内尖 ,下三角座前后压缩且下前尖退化 ,m3三叶。中国曾经记述的和被认为是裂齿类的古新世哺乳动物共有 9个属种 :Lofochaiusbrachyo dus、Meiostylodonzaoshiensis、Anchilestesimpolitus、Dysnoetodonminuta、Interogaledatangensis、Pletho rodonchienshanensis、Huananiusyoungi、Yuesthonyxtingae和Simplodonqianshanensis。经过仔细比较研究它们的齿列 ,作者认为 ,Lofochaius、Meiostylodon、Interogale、Plethorodon和Simplodon可能属于裂齿类 ,而Anchilestes、Dysnoetodon、Huananius和Yuesthonyx则可能与裂齿类没有很近的亲缘关系。广东南雄盆地上湖组Lofochaiusbrachyodus的P1和P2退化、P4有一定程度的臼齿化、外架窄、主尖锥状、前尖棱和后尖棱的颊侧端内收 ,显示了裂齿类的特点。湖南茶陵盆地枣市组Meiostylodonzaoshiensis的i2增大、上臼齿主尖锥状、柱尖和后附尖发育、前尖棱和后尖棱的颊侧?
A new genus of Paleocene split teeth in Anhui Buried Hill Basin is described, named Benaiusqianshuiensisgen. etp. Nov. Specimens were produced at the bottom of the lower part of Wanghudun Formation and were left mandibles with canines and intact cheek teeth. The main characteristics of the new species are: the individual is smaller, the lower dentition teeth 2 +? 1.4.4, i2 slightly increased, p1 exists but degenerated into a single and flat side, p3 no back apex, p4 times Molar and without under the tip, the lower triangular seat before and after compression and degradation of the next tip, m3 clover. There are nine genera of ancient Paleocene mammals recorded and thought to be split in China: Lofochaius brachyo dus, Meiostylodonzaoshiensis, Anchilestesimpolitus, Dysnoetodonminuta, Interogaledatangensis, Pletho rodonchienshanensis, Huananiusyoungi, Yuesthonyxtingae and Simplodonqianshanensis. After careful comparison of their dentition, the authors suggest that Lofochaius, Meiostylodon, Interogale, Plethorodon and Simplodon may belong to the class of split teeth, while Anchilestes, Dysnoetodon, Huananius and Yuesthonyx may not have close genetic relationship with split-type. The P1 and P2 of Lofochaius brachyodus in the Upper Lake Formation in the Nanxiong Basin of Guangdong were degraded. P4 had a certain degree of molar deformity, narrow ectocervix, primary conical, anterior and distal cusp ends, showing the presence of split teeth specialty. I2 in Meiostylodonzaoshiensis in Jujube City, Chaling Basin, Hunan Province increased. The maxillary protuberant conical, columnar and posterior apical development, the buccal side of the apical and posterior apices?