Irpiciporus pachyodon Spongipellis Elliptio Unio pictorum Pythia (gastropod) Borophagus Myliobatis Squalodon List of extinct cetaceans Hydnellum peckii List of the Cenozoic life of Maryland Irpiciporus Borophagus diversidens List of prehistoric cartilaginous fish genera Cephalodella Scaldicetus