A new basal hadrosauriform dinosaur (Ornithischia: Iguanodontia) from the Early Cretaceous of northwestern China

Abstract

A new hadrosauriform dinosaur, Jintasaurus meniscus gen. et sp. nov., is reported from the Lower Cretaceous Xinminpu Group of the Yujingzi Basin, Jiuquan area, Gansu Province, northwestern China. It is represented by an articulated posterior portion of the skull and is unique in having an extremely long, pendant and crescentic paroccipital process with its ventral tip projecting far beyond the ventral level of the occipital condyle. Phylogenetic analysis recovers Jintasaurus as the sister-taxon to Hadrosauroidea, more derived than other Early Cretaceous hadrosauriforms and Protohadros from the early Late Cretaceous of North America. This discovery adds one more close relative to Hadrosauroidea in Asia and supports an Asian origin for this group.