Phylum Mollusca Linnaeus, 1758 - molluscs Class Gastropoda Cuvier, 1795 - snails and slugs Subclass Prosobranchia Milne-Edwards, 1848 - prosobranchs see Class Gastropoda Cuvier, 1795 Order Caenogastropoda Cox, 1960 see Superorder Caenogastropoda Cox, 1960 Superfamily Rissooidea Gray, 1847 Family Caecidae Gray, 1850 - caecids 1 Subfamily Caecinae Gray, 1850