Phylum Mollusca Linnaeus, 1758 - molluscs
   Conchifera Gegenbaur, 1878 see Subphylum Conchifera Gegenbauer, 1878
     Cyrtosoma
       Class Gastropoda Cuvier, 1795 - snails and slugs
         Orthogastropoda Ponder & Lindberg, 1995 see Subclass Orthogastropoda Ponder & Lindberg, 1995
           1 Vetigastropoda Salvini-Plawen, 1980 see Order Vetigastropoda Salvini-Plawen, 1980
           2.1 Cocculinoidea Dall, 1882
           2.2.1 Neritimorpha Koken, 1896 see Order Neritimorpha Golikov & Starobogatov, 1975
           2.2.2 Apogastropoda Salvini-Plawen & Haszprunar, 1987