The taxonomy and phylogeny of Diopecephalus kochi (Wagner, 1837) and 'Germanodactylus rhamphastinus' (Wagner, 1851)

The Solnhofen pterosaurs Pterodactylus antiquus, Aerodactylus scolopaciceps, Diopecephalus kochi, Germanodactylus cristatus and Germanodactylus rhamphastinus all have complicated taxonomic histories. Species originally placed in the genus Pterodactylus, such as Aerodactylus scolopaciceps, Ardeadactylus longicollum, Cycnorhamphus suevicus and Germanodactylus cristatus possess apomorphies not observed in the type species of Pterodactylus, and consequently have been placed in new genera. The affinities of another Solnhofen pterosaur previously placed in Pterodactylus, Diopecephalus kochi, are less clear. It has been proposed that D. kochi is a juvenile specimen of Pterodactylus antiquus, or perhaps 'Germanodactylus rhamphastinus' specimens are mature examples of D. kochi. Furthermore, studies have suggested that 'Germanodactylus rhamphastinus' is not congeneric with the type species of Germanodactylus. Geometric morphometric analysis of prepubes and a cladistic analysis of the Pterosauria elucidate plesiomorphic and apomorphic conditions for basal Jurassic pterodactyloids. Germanodactylus is found to be a monotypic genus and Pterodactylus, Diopecephalus, and 'G. rhamphastinus' are found as distinct taxa belonging in individual genera, diagnosable using a combination of characters. Thus, Diopecephalus kochi is not demonstrated to be congeneric with Germanodactylus or Pterodactylus and is maintained as a valid taxon. 'G. rhamphastinus' is readily distinguishable from other Solnhofen pterosaur taxa, and a new genus is erected for its reception.