Polazzodus, gen. nov., a new pycnodont fish from the Late Cretaceous of northeastern Italy

Polazzodus coronatus, gen. et sp. nov., is a pycnodontiform fish from two proximate Late Cretaceous fossil sites near Polazzo, in northeastern Italy, where it is relatively abundant. Its autapomorphic characters are the presence of a distinctively shaped second dorsal ridge scale with an anterior projection; the presence of an olfactory fenestra on the premaxilla; an axe blade-like morphology of the maxilla; and the presence of a conspicuous posterodorsal process on the cleithrum. Polazzodus coronatus, gen. et sp. nov., is closely related to the pycnodontids Oropycnodus, Pycnodus, and probably 'Coelodus' gridelli and Tergestinia. Although their phylogenetic interrelationships will be tested when the last two forms are revised, Polazzodus coronatus is assigned to the subfamily Pycnodontinae within the Family Pycnodontidae, because it possesses the autapomorphies of both latter groups; for instance, the presence of an exposed part of the endocranium, without overlying dermal bones, which is an autapomorphy of the Pycnodontinae. The shape and large size of the supraoccipital bone in Polazzodus, together with the arrangement of the other occipital bones, indicates that this exposed portion of the endocranium is most likely formed by the endochondral supraoccipital bone.