Monolophosaurus jiangi Zhao and Currie, 1993

Age . Middle Jurassic.

Occurrence. Wucaiwan Formation, Xinjiang, China.

Diagnosis. Large midline crest on skull, formed by the premaxillae, nasals, lacrimals and anterior ends of the frontals.

Remarks. Monolophosaurus is the only theropod from the Middle Jurassic of China for which good skull material is known (Text-fig. 5d; Zhao and Currie 1993). Although its major apomorphic character is the presence of the unusual medial crest on the skull, the postcranium is sufficiently different from that of the probable contemporaneous taxa Gasosaurus, 4Szechuanosaurus' zigongensis, and Xuanhanosaurus to establish it as a separate genus beyond any reasonable doubt.