Osteology and phylogenetic relationships of Gregoriopycnodus bassanii gen. nov., a pycnodont fish (Pycnodontidae) from the marine Albian (Lower Cretaceous) of Pietraroja (southern Italy)

The osteology and the phylogenetic relationships of Gregoriopycnodus bassanii gen. nov., a pycnodont fish from the marine Albian (Lower Cretaceous) of Pietraroja (southern Italy), are studied in details. This fossil genus belongs to the family Pycnodontidae, as shown by the presence of a branched peniculus on the parietal. Gregoriopycnodus differs from the other genera of the family by its short and plate-like prefrontral that is partly fused to the mesethmoid. Within the family, the systematic position of Gregoriopycnodus is intermediate between that of Tepexichthys and Costapycnodus, on the one hand, and that of Proscinetes, on the other hand.