摘要
///Omeisaurus jiaoi, a new species of giant sauropod is described in this paper. The specimen (ZDM 5050)was discovered from the Xiashaximiao Formation of the Middle Jurassic of Zigong Dinosaur Museum, Sichuan Province. ZDM 5050 is a nearly complete skeleton.Its main features can be summarized as follows: dorsal vertebrae are tall and large. The anterior dorsal vertebrae(dorsals 1 to 6)are opisthocoelous. The pleurocoels of the dorsal vertebrate are well developed except on the 1stdorsal. The neural spines are club-like and the neural spines of the anterior dorsal vertebrae are not bifurcated. Caudal vertebrae are relatively short and thick. The anterior caudal vertebrae are slightly amphicoelous. The chevron of the 1stcaudal vertebrae is connected with the 1stcaudal and is shallow and small. Humerus is long and straight, with slighdy expanded proximal end and greatly expanded distal end. The deltopectoral crest is well-developed and relatively low. Femur is slender in shape, with greatly expanded proximal and distal ends. The fourth trochanter is well-developed.