Abstract: The crania of Xinpusaurus sp. from the Carnian Wayao Formation of Guanling, Guizhou Province is studied in detail and then compared with other two species of Xinpusaurus. The new specimen shows following similarities to other two species: the lateral view looks like a right-angled triangle when the mouth is closed; the frontage of the dentary forms a platform as a result of its bending; a significant curve exists at the end of the premaxilla; the posterior process of the rasal extends far away from the external naris; the post-lateral process of the premaxilla extends beyond the external naris. So it is assigned to be a Xinpusaurus. However, the specimen is still significantly different to other two species: the adult size is relatively larger; the tooth at the end of the premaxilla inclines posteriorly; the premaxilla is not excluded from the formation of the external naris; no tooth on the pterygoid; the prefrontal contacts with the nasal; no tooth on the maxilla and the back of the dentary. Because of the ill preservation of the specimen, the characters of the temporal region and the post cranial can not be identified, and it's assigned to an undefined species of Xinpusaurus.

Key words: Thalattosaurus, Xinpusaurus, Late Triassic, Guanling, Guizhou Province

摘要： 对产自贵州省关岭县晚三叠世卡尼期瓦窑组的一件新铺龙头骨标本进行了详细的描述，并和新铺龙属另外两种的标本进行了对比，认为该标本以下特征与其他新铺龙类似：上下颌咬合时头骨侧视呈直角三角形；齿骨前部由于弯曲形成一个平台；前颌骨末端形成明显的凹缘；鼻骨向后延伸至离外鼻孔较远处；前颌骨内侧突向后延伸至外鼻孔之后。因此将其归入新铺龙属。但其与其他两种存在以下明显区别：成年个体明显较大；前颌骨末端的牙齿倒伏方向向后；前颌骨参与了外鼻孔的形成；没有翼骨齿；前额骨与鼻骨接触；齿骨后端和上颌骨没有牙齿。由于标本保存不完整，重要的颅区骨骼和头后骨骼特征无法鉴定，因此暂将其归入一未定种。

关键词: 新铺龙, 海龙, 晚三叠世, 贵州关岭