Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, People's Republic of China.
College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
Biol Lett. 2022 Jul;18(7):20220222. doi: 10.1098/rsbl.2022.0222. Epub 2022 Jul 13.
Therapsids were widely distributed in Pangea in the late Permian. South Africa in Gondwana and Russia in Laurasia are the principal areas recording tetrapods (including therapsids) of this age. More recent field explorations have increased the importance of Chinese late Permian fossil assemblages. This is clearly reflected in the discovery of several new therocephalians from the Naobaogou Formation in Nei Mongol. Here, we report a therocephalian from that unit identified as a new species of the emblematic South African taxon . The new species, , is represented by a well-preserved skull and mandible showing a well-developed maxillary fossa and the absence of postcanine teeth. This is the third akidnognathid therocephalian recovered from the Naobaougou Formation, but oddly, the two basal Chinese akidnognathids previously known were recovered from a younger unit of the formation than the derived . This is the first time that the same therocephalian genus has been recorded in northern and southern continents, making the record of the Naobaougou Formation key to understanding the evolution of late Permian continental fauna in general, and of akidnognathid therocephalians in particular.
兽孔目动物在二叠纪晚期的泛古陆中广泛分布。冈瓦纳古陆的南非和劳亚古陆的俄罗斯是记录这个时代四足动物(包括兽孔目动物)的主要地区。最近的野外考察增加了中国晚二叠世化石组合的重要性。这一点在从内蒙古的那傲包沟组中发现的几个新兽头亚目动物中得到了明显的体现。在这里,我们报告了来自该单元的一个兽头亚目动物,被确定为具有代表性的南非分类单元的一个新种。这个新种,,以保存完好的头骨和下颌为代表,显示出发达的上颌窦和没有后齿。这是从那傲包沟组中回收的第三个似哺乳爬行动物,但奇怪的是,以前已知的两个基础似哺乳爬行动物是从该组的一个比衍生的更年轻的单元中回收的。这是第一次在南北大陆上记录到同一个兽头亚目属,这使得那傲包沟组的记录成为理解晚二叠世大陆动物群进化的关键,特别是似哺乳爬行动物的进化。