Phylum Mollusca Linnaeus, 1758 - molluscs Subphylum Conchifera Gegenbauer, 1878 Class Gastropoda Cuvier, 1795 - snails and slugs Subclass Orthogastropoda Ponder & Lindberg, 1995 Superorder Vetigastropoda Salvini-Plawen, 1980 see Order Vetigastropoda Salvini-Plawen, 1980 Superfamily Fissurelloidea Fleming, 1822 1 Family Fissurellidae Fleming, 1822 - keyhole limpets 2 Family Clypeosectidae McLean, 1989