Phylum Mollusca Linnaeus, 1758 - molluscs Conchifera Gegenbaur, 1878 see Subphylum Conchifera Gegenbauer, 1878 Cyrtosoma Class Gastropoda Cuvier, 1795 - snails and slugs Orthogastropoda Ponder & Lindberg, 1995 see Subclass Orthogastropoda Ponder & Lindberg, 1995 Neritimorpha Koken, 1896 see Order Neritimorpha Golikov & Starobogatov, 1975