Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, China.
College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing, China.
PeerJ. 2023 Jul 31;11:e15783. doi: 10.7717/peerj.15783. eCollection 2023.
is the first reported Chinese dicynodont, previously only known from Xinjiang. Here we refer two specimens from the Naobaogou Formation, Nei Mongol, China to based on the following features: squamosal separated from supraoccipital by tabular, tabular contacting opisthotic, sharp and thin lateral dentary shelf expanding anteriorly into a thick swelling, nasals fused as single element, rod-like medial bar formed by footplate of epipterygoid connecting to the parabasisphenoid and periotic medially. A new species, , is named based on the diagnostic characters on these two specimens such as distinct caniniform buttress lacking posteroventral furrow, naso-frontal suture forming an anterior directed sharp angle, and converging ventral ridges on posterior portion of anterior pterygoid rami. In , the epipterygoid posteromedially contacts the parabasisphenoid and the periotic as a rod-like bar, a unique morphology unknown in any other dicynodonts. This structure probably increases the stability of the palatal complex. A similar structure might also appear in other dicynodonts as a cartilage connection. The new occurrence of increases the diversity of the tetrapod assemblage from the Naobaogou Formation, and further strengthens the connection between the tetrapod faunas from Nei Mongol and Xinjiang. Based on the current record, is one of the few tetrapod genera which survived in the end-Permian mass extinction.
是首例报道的中国兽孔目动物，此前仅在新疆发现过。本文提到的来自内蒙古那傲堡沟组的两个标本，基于以下特征被归入：方骨与顶骨由方骨管隔开，方骨管与耳后骨接触，狭窄而薄的外侧下颌架向前扩展成一个厚实的隆起，鼻骨融合成单个元素，由后翼骨的基板连接到基蝶骨和耳骨内侧的棒状中轴形成，以上特征均与其他兽孔目动物不同。基于这两个标本的特征，如明显的犬齿状支撑物缺乏后腹沟、额鼻缝形成向前的锐角、前翼骨支后段的腹侧脊汇聚，我们命名了一个新种，。在中，后翼骨的后内侧与基蝶骨和耳骨接触形成棒状，这种独特的形态在其他兽孔目动物中尚未发现。这种结构可能增加了腭复合体的稳定性。这种结构可能也会出现在其他兽孔目动物中，作为软骨连接。的新出现增加了那傲堡沟组四足动物组合的多样性，并进一步加强了内蒙古和新疆四足动物群之间的联系。根据目前的记录，是少数在二叠纪末大灭绝中幸存下来的四足动物属之一。
