Many sauropod ghost lineages cross the Middle Jurassic, indicating a time interval that requires increased sampling. A wide taxonomic spectrum of sauropodomorphs is known from the Middle Jurassic of China, but the braincase of a  new sauropod, named here Nebulasaurus taito gen. et sp. nov., is distinct. Nebulasaurus is sister taxon to Spinophorosaurus from the Middle Jurassic of Africa and represents a clade of basal eusauropods previously unknown from Asia. The revised faunal list indicates dramatic transitions in sauropodomorph faunas from the Jurassic to Cretaceous of Asia; these are consistent with geographic isolation of Asia through the Late Jurassic. Non-sauropod sauropodomorphs, non-mamenchisaurid eusauropods (including basal macronarians), and mamenchisaurids successively replaced previous grades through the Jurassic, and titanosauriforms excluded all other sauropod lineages across the Jurassic–Cretaceous boundary.

Key words: Dinosauria, Sauropoda, Eusauropoda, Jurassic, China.

Lida Xing [xinglida@gmail.com] and Jianping Zhang [zhjping@cugb.edu.cn], School of the Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China; Tetsuto Miyashita [tetsuto@ualberta.ca] and Philip J. Currie [philip.currie@ualberta.ca], Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E9 Canada; Hailu You [youhailu@gmail.com] Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China; Zhiming Dong [dinodong@sina.com], Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China.