Gastropoda
      Caenogastropoda
                  Ptenoglossa
                              Epitonioidea
                                    Epitoniidae
                                    Janthinidae
                                    Nystiellidae
                              Eulimoidea
                                    Aclididae
                                    Eulimidae
                              Triphoroidea
                                    Cerithiopsidae
                                    Newtoniellidae
                                    Triphoridae