A new sauropod dinosaur (Dinosauria, Sauropoda) from the late Early Cretaceous of the Ruyang Basin (central China)

• We report a new sauropod dinosaur from the late Early Cretaceous of central China.
• Yunmenglong ruyangensis gen. et sp. nov. shares characters with Euhelopus, Qiaowanlong and Erketu.
• They may form a unique long-necked Asian group.
• The discovery of Yunmenglong provides a key role in our understanding of the long-necked dinosaurs' paleogeographical distribution and evolution.

A new long-necked sauropod dinosaur, Yunmenglong ruyangensis gen. et sp. nov., is erected on the basis of an incomplete skeleton from the late Early Cretaceous Haoling Formation of the Ruyang Basin, Henan Province. The characters of the anterior cervical vertebrae, the shape of the neural canal of the dorsal vertebra and the ball-shaped distal end of the neural spine of caudal vertebrae with coarse surfaces differ from other long-necked sauropod dinosaurs. The new genus has characters in common with both Euhelopus and Erketu; it represents the first long-necked sauropod dinosaur recorded from central China to date. The rod-like, well-developed epipophyses and the pleurocoels on the cervical vertebrae indicate that it may be close to Euhelopus, an observation also confirmed by a phylogenetic analysis, which shows that Erketu, Yunmenglong and Qiaowanlong form a clade, and are more derived than Euhelopus.