New ornithischian dinosaur material from the Lower Jurassic Lufeng Formation of China

摘要

Published records of ornithischian dinosaurs from the Lower Jurassic Lufeng Formation are extremely rare. Here we describe a new ornithischian specimen, FMNH CUP 2338, consisting of an articulated lower tibia and fibula, ankle, and pes from the Zhangjiawa Member of the Lufeng Formation. Preserved character-states are largely plesiomorphic for Ornithischia; our analysis indicates that the specimen represents an indeterminate basal ornithischian dinosaur. Reanalysis of the other known ornithischian specimens from the Lufeng Formation indicates that they are either not ornithischians, or are assignable to Thyreophora or Ornithischia indet. The abundance of ornithischians in the Lufeng Formation is unusually low compared with other well-known Early Jurassic ornithischian-bearing terrestrial tetrapod assemblages.