A revision of Sanpasaurus yaoi Young, 1944 from the Early Jurassic of China, and its relevance to the early evolution of Sauropoda (Dinosauria)

摘要: The Early Jurassic of China has long been recognized for its diverse array sauropodomorph dinosaurs. However, the contribution this record to our understanding early sauropod evolution is complicated by a dearth information on important transitional taxa. We present revision poorly known taxon Sanpasaurus yaoi Young, 1944 from late Ziliujing Formation Sichuan Province, southwest China. Initially described as remains an ornithopod ornithischian, we demonstrate that material catalogued IVPP V156 unambiguously referable Sauropoda. Although represented multiple individuals equivocal association, nonetheless diagnosable with respect autapomorphic feature holotypic dorsal vertebral series. Additional thought be collected type locality tentatively referred Sanpasaurus. If correctly attributed, second autapomorphy in humerus. presence dorsoventrally compressed pedal ungual particular interest, taxa possessing typically ‘vulcanodontid’ character exhibiting much broader geographic distribution than previously thought. Furthermore, association trait other features are broadly characteristic basal eusauropods underscores mosaic nature sauropod–eusauropod transition. Our palaeobiogeographic implications sauropods, evidence group maintained cosmopolitan Pangaean distribution.