Braincase Anatomy of the Basal Theropod Sinosaurus from the Early Jurassic of China  

作　　者：XING Lida Ariana PAULINA-CARABAJAL Philip J.CURRIE XU Xing ZHANG Jianping WANG Tao Michael E.BURNS DONG Zhiming 

机构地区：[1]School of the Earth Sciences and Resources, China University of Geosciences [2]Museo Carmen Funes, Consejo Nacional de Investigaciones Científicas y Tecnológicas,Av.Córdoba 55 (8318),Plaza Huincul, Neuquén, Argentina [3]University of Alberta, CW405 Biological Sciences Building,Edmonton, Alberta T6G 2E9, Canada [4]Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences [5]Lufeng Land and Resources Bureau

出　　处：《Acta Geologica Sinica(English Edition)》2014年第6期1653-1664,共12页地质学报（英文版）

摘　　要：The neuroanatomy of the mid-sized theropod Sinosaurus triassicus from the Lower Jurassic Lufeng Formation, Lufeng Basin in Yunnan Province, China was studied using X-ray computed tomography. The braincase is characterized by a large supraoccipital knob that is capped by a posterior projection of the parietal and two external foramina for the caudal middle cerebral vein, which is completely enclosed by the supraoccipital. The basicranium has well defined, short basipterygoid processes that project ventral to the basal tubera. The basisphenoid is expanded, projects posteroventrally, and is pierced by four pneumatic recesses. The endocranial morphology resembles that observed in other basal theropods—in particular some allosauroids—and has a strongly marked pontine flexure and a large dorsal expansion. The inner ear morphology is also similar to that observed in other basal theropods, with slender semicircular canals. The anterior semicircular canal is 20% larger than the posterior semicircular canal, and the angle formed between them is less than 90° when seen in dorsal view.The neuroanatomy of the mid-sized theropod Sinosaurus triassicus from the Lower Jurassic Lufeng Formation, Lufeng Basin in Yunnan Province, China was studied using X-ray computed tomography. The braincase is characterized by a large supraoccipital knob that is capped by a posterior projection of the parietal and two external foramina for the caudal middle cerebral vein, which is completely enclosed by the supraoccipital. The basicranium has well defined, short basipterygoid processes that project ventral to the basal tubera. The basisphenoid is expanded, projects posteroventrally, and is pierced by four pneumatic recesses. The endocranial morphology resembles that observed in other basal theropods—in particular some allosauroids—and has a strongly marked pontine flexure and a large dorsal expansion. The inner ear morphology is also similar to that observed in other basal theropods, with slender semicircular canals. The anterior semicircular canal is 20% larger than the posterior semicircular canal, and the angle formed between them is less than 90° when seen in dorsal view.

关 键 词：NEUROANATOMY paleoneurology DINOSAUR inner ear pneumaticity Early Jurassic Yunnan 

分 类 号：Q915[天文地球—古生物学与地层学]