Class [Cephalopoda] Cuvier, 1795 - cephalopods 1 Subclass †Ellesmeroceratoidea 2 Subclass †Endoceratoidea Teichert, 1933 3 Subclass †Actinoceratoidea Teichert et al., 1964 4 Subclass Nautiloidea Agassiz, 1848 5 Subclass †Orthoceratoidea McCoy, 1844