Phylum Mollusca Linnaeus, 1758 - molluscs
   Class Gastropoda Cuvier, 1795 - snails and slugs
     Subclass Prosobranchia Milne-Edwards, 1848 - prosobranchs see Class Gastropoda Cuvier, 1795
       Order Caenogastropoda Cox, 1960 see Superorder Caenogastropoda Cox, 1960
         Suborder Neotaenioglossa Haller, 1882 see Order Sorbeoconcha Ponder & Lindberg, 1997
           Superfamily Littorinoidea Children, 1834
             Family Littorinidae Children, 1834 - periwinkles
               Subfamily Risellinae Kesteven, 1903 [monotypic] see Subfamily Lacuninae Gray, 1857
                 Genus Peasiella Nevill, 1885