Mollusca Linnaeus, 1758 - molluscs see Phylum Mollusca Linnaeus, 1758
   Gastropoda Cuvier, 1795 see Class Gastropoda Cuvier, 1795
     Clade Caenogastropoda Cox, 1960 see Superorder Caenogastropoda Cox, 1960
       Clade Sorbeoconcha Ponder & Lindberg, 1997 see Order Sorbeoconcha Ponder & Lindberg, 1997
         Clade Hypsogastropoda Ponder & Lindberg, 1997 see Suborder Hypsogastropoda Ponder & Lindberg, 1997
           "Group" Ptenoglossa Gray, 1853 see Infraorder Ptenoglossa Gray, 1853
             Superfamily Epitonioidea Berry, 1910 (1812)
               Family Nystiellidae Clench & Turner, 1952