Phylum [Mollusca] Linnaeus, 1758 - molluscs
   Class Gastropoda Cuvier, 1795 - snails and slugs
     Subclass Prosobranchia Milne-Edwards, 1848 - prosobranchs see Class Gastropoda Cuvier, 1795
       Order Heterogastropoda see Superfamily Heterogastropoda
         Suborder Ptenoglossa Gray, 1853 see Infraorder Ptenoglossa Gray, 1853
           Superfamily Triphoracea see Superfamily Triphoroidea Gray, 1847
             Family Triphoridae Gray, 1847
               Subfamily Mastoniinae Kosuge, 1966 see Subfamily Triphorinae Gray, 1847
                 1 Genus Inella Bayle, 1879
                 2 Genus Mastonia Hinds, 1843
                 3 Genus Tetraphora Laseron, 1958
                 4 Genus Viriola Jousseaume, 1884