†family Hadrosteidae Gross 1932 (armour-plated fish)
Placodermi - Phlyctaeniiformes - Hadrosteidae
Parent taxon: Aspinothoracidi according to R. van der Laan 2019
Sister taxa: Brachydeiridae, Braunosteidae, Bulbocanthidae, Dinichthyidae, Gorgonichthys, Heintzichthys, Leiosteidae, Leptosteidae, Titanichthyidae
Subtaxa: Hadrosteus
Type: Hadrosteus
Ecology: nektonic carnivore
Distribution: found only at Bad Wildungen site (Devonian of Germany)