Kingdom Animalia Linnaeus, 1758 - animals Phylum Mollusca Linnaeus, 1758 - molluscs Subphylum Cyrtosoma Runnegar & Pojeta Jr., 1974 see Phylum Mollusca Linnaeus, 1758 Class Cephalopoda Cuvier, 1795 - cephalopods Subclass †Ammonoidea Zittel, 1884 Genus †Leptoceras Uhlig, 1883