Phylum [Mollusca] Linnaeus, 1758 - molluscs
   Class Gastropoda Cuvier, 1795 - snails and slugs
     Subclass Prosobranchia Milne-Edwards, 1848 - prosobranchs see Class Gastropoda Cuvier, 1795
       Order Archaegastropoda see Order Archaeogastropoda Thiele, 1925
         Superfamily Fissurellacea Fleming, 1822 see Superfamily Fissurelloidea Fleming, 1822
           Family Fissurellidae Fleming, 1822 - keyhole limpets
             Subfamily Emarginulinae Children, 1834
               Genus Hemitoma Swainson, 1840
                 Subgenus Hemitoma (Hemitoma) Swainson, 1840