Eukaryota Chatton, 1925 - eukaryotes see Domain Eukaryota Chatton, 1925
   Opisthokonta Cavalier-Smith, 1987 - opisthokonts see Clade Opisthokonta Cavalier-Smith 1987, nom. cl. inval.
     Metazoa Haeckel 1874 - multicellular animals see Kingdom Animalia Linnaeus, 1758
       Eumetazoa Bütschli, 1910 - eumetazoans
         Triploblastica see [unranked] Bilateria Hatschek, 1888
           Bilateria Hatschek, 1888 - bilaterians see Subkingdom Bilateria Hatschek, 1888
             Protostomia Grobben, 1908 see Infrakingdom Protostomia Grobben, 1908
               Lophotrochozoa Halanych, Bacheller, Aguinaldo, Liva, Hillis & Lake 1995 - lophotrochozoans
                 Spiralia Schleip, 1929 - spiralians see Superphylum Spiralia Schleip, 1929
                   Trochozoa Beklemischev, 1944 - trochozoans
                     Phylum Mollusca Linnaeus, 1758 - molluscs
                       Eumollusca
                         Conchifera Gegenbaur, 1878 see Subphylum Conchifera Gegenbauer, 1878
                           Ganglioneura Rudophi, 1812
                             Rhacopoda see [unranked] Conchifera Gegenbaur, 1878
                               Class Gastropoda Cuvier, 1795 - snails and slugs
                                 opisthobranchs see Order Opisthobranchia Milne-Edwards, 1848
                                   Suborder Cephalaspidea Fischer, 1883 - bubble snails see Order Cephalaspidea Fischer, 1883
                                     1 Family Ringiculidae Philippi, 1853
                                     2 Family Acteonidae d'Orbigny, 1843, nom. protect. - bubble shells
                                     3 Family Hydatinidae Pilsbry, 1895, nom. illeg. see Family Aplustridae Gray, 1847
                                     4 Family Bullidae Gray, 1827
                                     5 Family Haminoeidae Pilsbry, 1895
                                     6 Family Cylichnidae Adams & Adams, 1854
                                     7 Family Retusidae Thiele, 1925