Dilophosauridae

Classification

In 2019, paleontologists Marion Zahner and Winand Brinkmann found the members of the Dilophosauridae to be successive basal sister taxa of the Averostra rather than a monophyletic clade (a natural group), but noted that some of their analyses did find the group valid, containing Dilophosaurus, Dracovenator, Cryolophosaurus, and possibly Notatesseraeraptor as the basal-most member. They therefore provided a diagnosis for the Dilophosauridae, based on features in the lower jaw. In the phylogenetic analysis accompanying their 2020 redescription, Marsh and Rowe found all specimens of Dilophosaurus to form a monophyletic group, sister to Averostra, and more derived than Cryolophosaurus. Their analysis did not find support for Dilophosauridae, and they suggested cranial crests were a plesiomorphic (ancestral) trait of Ceratosauria and Tetanurae.