Diopecephalus is a genus of pterodactyloid pterosaur from the Lower Tithonian (Upper Jurassic) of the Lithographic Limestone, Bavaria, Germany.

[1] Like many pterosaurs, it has had a confusing taxonomic history, being given names by various authorities which identify it with four other genera: In 2017, Steven U. Vidovic and David M. Martill resurrected the genus Diopecephalus for Pterodactylus kochi,[2] a taxon generally regarded as synonymous with Pterodactylus antiquus.

[4] Vidovic and Martill's suggestion that kochi is taxonomically distinct rely on a combination of characteristics rather than autapomorphies, including features such as the slope of the snout and the rounded shape of the back of the skull, the shape and distribution of teeth, and the length and depth of the cervical vertebrae.

[2] Most of these features are typical for Pterodactylus or are known to vary with growth stage[1][3][4] and, as per Vidovic and Martill's previous work with another resurrected Pterodactylus-like genus, Aerodactylus, arguments discounting individual variation and preservational factors (e.g., specimen orientation, compression) from true taxonomic distinction were not provided.

[6] Below is a cladogram showing the results of a phylogenetic analysis presented by Andres, Clark & Xu, 2014.