分类： 地球科学 >> 地质学 提交时间： 2017-09-28 合作期刊: 《古脊椎动物学报》
摘要： 描述了在兰州盆地渐新统韩家井组底部的黄砂层中新发现的巨犀化石：黄河巨犀(Paraceratherium huangheense sp. nov.) (新种), 该化石产出层位的古地磁年龄为距今31.5Ma。新种主要特征为：P2之前无齿槽痕迹，一对下门齿粗壮，互相靠近，向前平伸且略微上翘，下颏孔位于p3之下，水平支下缘平直， p2前的齿隙部分向上隆起，下颌角圆钝，上升支后缘斜向后上方，齿式： ?·?·3·3/1·0·3·3。除个体较大、下颌后缘有所不同之外，其下颌的总体特征与巴基斯坦的Paraceratherium bugtiense最为接近，显示两者可能具有较近的亲缘关系。新标本的发现为确定经典的Dera Bugti地点产大巨犀化石层位的年代提供了新的证据，并为青藏高原的隆升讨论提供了新的哺乳动物化石证据。
分类： 地球科学 >> 地质学 提交时间： 2017-08-11 合作期刊: 《古脊椎动物学报》
摘要： This paper describes some micromammal fossils which were excavated from the South Longyadong Cave in the Luonan Basin, eastern Qinling Mountains of Shaanxi Province, central China. The fauna include 15 mammals consisting by Scapanulus oweni, Nasillus andersoni, Uropsilinae gen. et sp. indet., Soriculus sp., Ochotona cf. O. alpina, Belomys parapearsoni, Allocricetus ehiki, Proedromys bedfordi, Allophaiomys deucalion, Eospalax sp., Niviventer preconfucianus, Apodemus asianicus, Apodemus sp., Hystrix brachyura subcristata, Trogontherium cuvieri. Among them, the Nasillus andersoni and the Ochotona cf. O. alpina are the newly discovered fossil species. The fossil assemblage characteristics of newly micromammal faunal is similar to the North Longyadong Cave Fauna, and the geological age should not be later than early Middle Pleistocene. It might be a fauna of late Early Pleistocene. But in recent years, the thermoluminescence age of fossiliferous strata corresponding are 356.6±17.8 kaBP, 273.9±13.7 kaBP and 210.5±10.5 kaBP. The fauna is including both the south and the north animals, the animal combination obviously has the characteristics of the transition between the south and the north of China. 描述了1995~1997年东秦岭山地洛南盆地龙牙南洞洞穴遗址中发掘出土的小哺乳动物化石，包括甘肃鼹Scapanulus oweni, 峨眉鼩鼹Nasillus andersoni, 鼩鼹(属种未定) Uropsilinae gen. et sp. indet., 长尾鼩鼱Soriculus sp., 似高山鼠兔Ochotona cf. O. alpina, 偏皮氏毛耳飞鼠Belomys parapearsoni, 艾克氏异仓鼠Allocricetus ehiki, 沟牙田鼠Proedromys bedfordi, 欧洲异费鼠Allophaiomys deucalion, 始鼢鼠Eospalax sp., 先社鼠Niviventer preconfucianus, 亚洲姬鼠Apodemus asianicus, 姬鼠Apodemus sp., 马来豪猪(华南亚种) Hystrix brachyura subcristata, 居氏大河狸Trogontherium cuvieri等。该动物群同时包括南方型和北方型动物，其动物组合具有明显的南北过渡地带的特征。其中峨眉鼩鼹和似高山鼠兔为新发现的化石种。新发现的小哺乳动物化石组合类似于龙牙北洞，显示出比较古老的性质，时代上多为早更新世晚期或中更新世早期，但龙牙南洞遗址含化石地层对应的热释光(TL)年龄结果分别为(356.6±7.8) kaBP, (273.9±3.7) kaBP和(210.5±0.5) kaBP, 最近新的回授光释光(TT-OSL)测年数据进一步验证了热释光测年结果，获得的地层年代亦为距今40~20万年左右。
分类： 地球科学 >> 地质学 提交时间： 2017-08-11 合作期刊: 《古脊椎动物学报》
摘要： Sabertooth cats were extinct carnivorans that have attracted great attention and controversy because of their unique dental morphology representing an entirely extinct mode of feeding specialization. Some of them are lion-sized or tiger-sized carnivorans who are widely interpreted as hunters of larger and more powerful preys than those of their modern nonsaber-toothed relatives. We report the discovery of a large sabertooth cat skull of Machairodus horribilis from the Late Miocene of northwestern China. It shares some characteristics with derived sabertooth cats, but also is similar to extant pantherines in some cranial characters. A functional morphological analysis suggests that it differed from most other machairodont felids and had a limited gape to hunt smaller preys. Its anatomical features provide new evidence for the diversity of killing bites even within in the largest saber-toothed carnivorans and offer an additional mechanism for the mosaic evolution leading to functional and morphological diversity in sabertooth cats. 剑齿虎是一类绝灭的食肉目动物，由于其独特的牙齿形态代表了已完全消失的特化取食方式而引起了极大的关注和争论。一些剑齿虎是狮子体型或老虎体型的食肉动物，它们被广泛认为能够比其不具剑形犬齿的现代近亲捕杀更大和更强壮的猎物。本文报道在甘肃省晚中新世地层中发现的一具属于恐剑齿虎(Machairodus horribilis)的大型头骨。这件标本的一些特征与进步的剑齿虎相同，但在某些头骨性状上则与现生的豹亚科种类相似。不同于其他大多数剑齿虎，功能形态分析指示该剑齿虎的口部张开程度受到限制，因此只能捕猎相对较小的猎物。这具头骨的解剖特征为证明即使在最大的具剑形犬齿的食肉目动物中也存在捕猎咬杀方式的多样性提供了新的证据，并揭示了在剑齿虎中导致功能和形态多样性镶嵌进化的另一种机制。
分类： 地球科学 >> 地质学 提交时间： 2017-08-08 合作期刊: 《古脊椎动物学报》
摘要： Four types of footprints of carnivorous dinosaurs have been found from the Yan’an Formation of early Middle Jurassic in Zizhou County, Shaanxi, China. From the top to bottom interval, the four types of footprints discovered at five layers in a 1.7 m thick stratum are as follows: 1) the large tridactyl footprints in the fifth layer (e, top) belong to Zizhoupus wangi ichnogen. et ichnosp. nov.; 2) the medium tridactyl footprints in the third and fourth layers (c–d) belong to Changpeipus longweimaoensis ichnosp. nov.; 3) small tridactyl or tetradactyl footprints in the second layer (b) belong to Shensipus xiaoliheensis ichnosp. nov. and 4) small tridactyl footprints in the frst layer (a, bottom) belong to Shensipus tungchuanensis.
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