Dongbeititan dongi, the First Sauropod Dinosaur from the Lower Cretaceous Jehol Group of Western Liaoning Province, China

Abstract:We herein describe a partial postcranial skeleton of a sauropod dinosaur recovered from the Lower Cretaceous Jehol Group in the Beipiao area of western Liaoning Province, northeastern China. A suite of features it possesses, including the camellate internal structure of its presacral elements, the existence of pneumatocoels on the proximal ends of the dorsal ribs, and especially the medially deflected proximal portion of the femur, definitively establish the titanosauriform affinities of the specimen. It differs from other titanosauriforms in having a craniocaudally elongate coracoid with a squared cranioventral extreme and a long, smooth, and slightly convex acetabular edge of the pubis. It represents a new taxon,Dongbeititan dongigen. et sp. nov. Comparative studies suggest thatDongbeititanis a basal titanosauriform, more derived thanEuhelopus, Fusuisaurus, andHuanghetitan, but less derived thanGobititanandJiutaisaurus. Dongbeititanrepresents the first sauropod dinosaur reported from the Lower Cretaceous Jehol Group of western Liaoning Province.