Cerithiidae Family Batillariidae † Family Brachytrematidae † Family Cassiopidae Family Dialidae Family Diastomatidae † Family Eustomatidae † Family Ladinulidae † Family Lanascalidae Family Litiopidae † Family Maoraxidae Family Melanopsidae † Family Metacerithiidae Family Modulidae Family Pachychilidae Family Paludomidae Family Planaxidae Family Pleuroceridae † Family Popenellidae Family Potamididae † Family Procerithiidae - If the genus Argyropeza is placed in the Procerithiidae, then this family is not all fossil. † Family Prostyliferidae † Family Propupaspiridae Family Scaliolidae Family Siliquariidae † Family Terebrellidae - not a valid name Family Thiaridae Family Turritellidae Superfamily Campaniloidea Family Campanilidae Family Ampullinidae Family Plesiotrochidae † Family Trypanaxidae Clade Hypsogastropoda Contains the clades Littorinimorpha, Neogastropoda and the informal group Ptenoglossa. Not allocated to a superfamily † Family Coelostylinidae † Family Maturifusidae † Family Pommerozygiidae † Family Settsassiidae Clade Littorinimorpha Superfamily Calyptraeoidea Family Calyptraeidae Superfamily Capuloidea Family Capulidae Superfamily Cingulopsoidea Family Cingulopsidae Family Eatoniellidae Family Rastodentidae Superfamliy Cypraeoidea Family Cypraeidae Family Ovulidae Superfamily Ficoidea Family Ficidae Superfamily Littorinoidea Family Littorinidae † Family Bohaispiridae Family Pickworthiidae Family Pomatiidae † Family Purpurinidae Family Skeneopsidae † Family Tripartellidae Family Zerotulidae Superfamily Naticoidea Family Naticidae Superfamily Pterotracheoidea Family Pterotracheidae Family Atlantidae † Family Bellerophinidae Family Carinariidae Superfamily Rissooidea Family Rissoidae Family Amnicolidae Family Anabathridae Family Assimineidae Family Barleeiidae Family Bithyniidae Family Caecidae Family Calopiidae Family Cochliopidae Family Elachisinidae Family Emblandidae Family Epigridae Family Falsicingulidae Family Helicostoidae Family Hydrobiidae Family Hydrococcidae Family Iravadiidae Family Lithoglyphidae † Family Mesocochliopidae Family Moitessieriidae † Family Palaeorissoinidae Family Pomatiopsidae Family Stenothyridae Family Tornidae Family Truncatellidae Superfamily Stromboidea Family Strombidae Family Aporrhaidae † Family Colombellinidae † Family Pugnellidae Family Rostellariidae Family Seraphsidae Family Struthiolariidae † Family Thersiteidae † Family Tylostomatidae Superfamily Tonnoidea Family Tonnidae Family Bursidae Family Laubierinidae Family Personidae Family Pisanianuridae Family Ranellidae Family Cassidae Superfamily Vanikoroidea Family Vanikoridae Family Haloceratidae Family Hipponicidae † Family Omalaxidae Superfamily Velutinoidea Family Velutinidae Family Triviidae Superfamily Vermetoidea Family Vermetidae Superfamily Xenophoroidea Family Xenophoridae † Family Lamelliphoridae Informal group Ptenoglossa Superfamily Epitonioidea Family Epitoniidae Family Janthinidae Family Nystiellidae Superfamily Eulimoidea Family Eulimidae Family Aclididae Superfamily Triphoroidea Family Triphoridae Family Cerithiopsidae Family Newtoniellidae Clade Neogastropoda Unassigned to a superfamily † Family Johnwyattiidae † Family Perissityidae † Family Sarganidae † Family Speightiidae † Family Taiomidae † Family Weeksiidae Superfamily Buccinoidea Family Buccinidae Family Colubrariidae Family Columbellidae Family Fasciolariidae Family Nassariidae Family Melongenidae Superfamily Muricoidea Family Muricidae Family Babyloniidae Family Costellariidae Family Cystiscidae Family Harpidae Family Marginellidae Family Mitridae † Family Pholidotomidae Family Pleioptygmatidae Family