vertebrates Lamarck, 1801 - vertebrates see Infraphylum Vertebrata Lamarck, 1801 Class †Pteraspidomorphi Goodrich, 1909 see Class Pteraspidomorpha Subclass †Heterostraci Lankester, 1868 Order †Cyathaspidiformes Kiaer, 1930 Family †Irregulareaspididae Denison, 1964 see Subfamily Irregulareaspidinae Denison, 1964 1 Genus †Irregulareaspis Zych, 1931