Abstract Early-diverging sauropodomorph dinosaurs are abundant in the Lower Jurassic Lufeng Formation of Lufeng area of Yunnan Province, southwestern China. However, the fossil records of this group remain relatively scarce in other regions of China. Here we describe a new sauropodomorph, Xiangyunloong fengming gen. et sp. nov., based on recently collected material from the Lower Jurassic Fengjiahe Formation of Xiangyun County of Dali Bai Autonomous Prefecture of Yunnan Province, which is about 200 km west to the Lufeng dinosaur fossil sites. Xiangyunloong can be diagnosed by several unique features such as lateral expansion developed at the middle region of the dorsal end of cervical neural spines, heightened hyposphene of dorsal vertebrae, and ilium with anteroposteriorly reduced but laterally and ventrally flaring supracetabular crest. Phylogenetic analysis recovers Xiangyunloong at a position between Massospondylidae and Sauropodiformes, and within an unresolved clade together with Xingxiulong chengi and Xingxiulong yueorum. Nonetheless, Xiangyunloong exhibits significant morphological distinctions from Xingxiulong and other early-diverging sauropodomorphs, supporting its designation as a new genus. The discovery of Xiangyunloong not only further expands the known taxonomic composition of Early Jurassic sauropodomorphs in southwestern China, but also enhances our understanding of the diversity, distribution and evolutionary history of this group.
Hu et al. (Wed,) studied this question.