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
             Family Fissurellidae Fleming, 1822 - keyhole limpets
               1 Subfamily Diodorinae Odhner, 1932 see Tribe Diodorini Odhner, 1932
               2 Subfamily Emarginulinae Children, 1834
               3 Subfamily Fissurellidinae Pilsbry, 1890, orth. inval. see Subfamily Fissurellideinae Pilsbry, 1890
               4 Subfamily Fissurellinae Fleming, 1822
               5 Subfamily Hemitominae Kuroda, Habe & Oyama, 1971 see Tribe Emarginulini Children, 1834
               6 Subfamily Scutinae Christiaens, 1973 see Tribe Scutini Christiaens, 1973