Dinichthyidae (Placodermi): A paleontological fiction?

Dinichthyidae has historically been a repository for a number of large pachyosteomorph arthrodires with questions raised on several occasions concerning the validity of this family. A cladistic analysis of dinichthyid arthrodires results in a revision of basal pachyosteomorph arthrodires. We amend the families Dinichthyidae, Dunkleosteidae, and Panxiosteidae with Dinichthys (Dinichthyidae, in part), Hadrosteus, Heintzichthys, Gorgonichthys, and Holdenius assigned to Aspinothoracidi. Dunkleosteus is rediagnosed and united with Eastmanosteus, Golshanichthys, Hussakofia, and Westralichthys in Dunkleosteidae. Janiosteus, and possibly Plourdosteus are united in Panxiosteidae as sister group to Dunkleosteidae. Finally, we refer Kiangyousteus, formerly a dinichthyid arthrodire, to Pachyosteomorphi incertae sedis.