Class gastropoda

Order Patellogastropoda
- - Superfamily Lottioidea
    - Lottiidae
    - Acmaeidae
    - Lepetidae
  - Superfamily Nacelloidea
    - Nacellidae
  - Superfamily Patelloidea
    - Patellidae
Order Cocculiniformia
- - - Superfamily Lepetelloidea
      - Addisoniidae
Order Neritoida
- - - Superfamily Neritoidea
      - Neritidae
      - Neritopsidae
      - Phenacolepadidae
Order Neomphalida
- - - Superfamily Neomphaloidea
      - Neomphalidae
Order Vetigastropoda
- - - Superfamily Pleurotomarioidea
      - Pleurotomariidae
      - Scissurellidae
      - Haliotidae
    - Superfamily Fissurelloidea
      - Fissurellidae
    - Superfamily Trochoidea
      - Trochidae
        
        Trochinae
        
        Calliostomatinae
        
        Stomatellinae
      - Turbinidae
        
        Turbininae
        
        Angariinae
        
        Liotiinae
        
        Phasianellinae
      - Skeneidae
    - Superfamily Seguenzioidea
      - Seguenziidae
Order Caenogastropoda
- Suborder Neotaenioglossa
  - Infraorder Discopoda
    - Superfamily Loxonematoidea
      - Abyssochrysidae
    - Superfamily Cerithioidea
      - Campanilidae
      - Diastomatidae
      - Dialidae
      - Litiopidae
      - Obtortionidae
      - Scaliolidae
      - Cerithiidae
      - Cerithideidae
      - Potamididae
      - Batillariidae
      - Fossaridae
      - Planaxidae
      - Modulidae
      - Turritellidae
      - Siliquariidae
    - Superfamily Vermetoidea
      - Vermetidae
    - Superfamily Littorinoidea
      - Littorinidae
      - Skeneopsidae
    - Superfamily Cingulopsoidea
      - Cingulopsidae
      - Eatoniellidae
    - Superfamily Rissooidea
      - Anabathridae
      - Barleeidae
      - Emblandidae
      - Caecidae
      - Elachisinidae
      - Epigridae
      - Falsicingulidae
      - Iravadiidae
      - Rissoidae
      - Assimineidae
      - Truncatellidae
      - Tornidae
      - Vitrinellidae
    - Superfamily Stromboidea
      - Aporrhaidae
      - Strombidae
      - Struthiolariidae
      - Seraphidae
    - Superfamily Xenophoroidea
      - Xenophoridae
    - Superfamily Calyptraeoidea
      - Calyptraeidae
      - Capulidae
    - Superfamily Vanikoroidea
      - Vanikoridae
      - Hipponicidae
    - Superfamily Cypraeoidea
      - Cypraeidae
      - Ovulidae
        
        Ovulinae
        
        Eocypraeinae
    - Superfamily Velutinoidea
      - Triviidae
        
        Triviinae
        
        Eratoinae
      - Velutinidae
    - Superfamily Naticoidea
      - Naticidae
    - Superfamily Tonnoidea
      - Cassidae
      - Bursidae
      - Personidae
      - Ranellidae
      - Ficidae
      - Tonnidae
      - Laubierinidae
  - Infraorder Heteropoda
    - Superfamily Carinarioidea
      - Atlantidae
      - Carinariidae
  - Infraorder Ptenoglossa
    - Superfamily Triphoroidea
      - Triphoridae
      - Cerithiopsidae
      - Triforidae
    - Superfamily Epitonioidea
      - Epitoniidae
      - Aclididae
      - Janthinidae
    - Superfamily Eulimoidea
      - Eulimidae
- Suborder Neogastropoda
  - - Superfamily Muricoidea
      - Muricidae
        
        Muricinae
        
        Thaidinae
        
        Coralliophilinae
      - Turbinellidae
        
        Turbinellinae
        
        Columbariinae
        
        Vasinae
      - Buccinidae
      - Fasciolariidae
      - Melongenidae
      - Nassariidae
      - Columbellidae
      - Harpidae
        
        Harpinae
        
        Moruminae
      - Marginellidae
      - Cystiscidae
      - Pleioptygmatidae
      - Mitridae
      - Costellariidae
      - Olividae
        
        Olivinae
        
        Ancillinae
      - Volutidae
      - Volutomitridae
    - Superfamily Cancellarioidea
      - Cancellariidae
    - Superfamily Conoidea
      - Conidae
      - Terebridae
      - Turridae
        
        Turrinae
        
        Borsoniinae
        
        Cochlespirinae
        
        Crassispirinae
        
        Daphnellinae
        
        Drilliinae
        
        Mangeliinae
Order Heterostropha
- - - Superfamily Valvatoidea
      - Orbitestellidae
    - Superfamily Rissoelloidea
      - Rissoellidae
    - Superfamily Omalogyroidea
      - Omalogyridae
    - Superfamily Architectonicoidea
      - Architectonicidae
      - Mathildidae
    - Superfamily Pyramidelloidea
      - Pyramidellidae
      - Amathinidae
Order Opisthobranchia
- Suborder Cephalaspidea
  - - Superfamily Ringiculoidea
      - Ringiculidae
    - Superfamily Acteonoidea
      - Acteonidae
      - Bullinidae
      - Hydatinidae
    - Superfamily Philinoidea
      - Philinidae
      - Cylichnidae
    - Superfamily Retusoidea
      - Retusidae
    - Superfamily Diaphanoidea
      - Diaphanidae
    - Superfamily Bulloidea
      - Bullidae
    - Superfamily Haminoeoidea
      - Haminoeidae
    - Superfamily Cylindrobulloidea
      - Cylindrobullidae
Suborder Anaspidea
- - Superfamily Aplysioidea
    - Aplysiidae
    - Akeridae
Suborder Sacoglossa
- - Superfamily Julioidea
    - Juliidae
  - Superfamily Oxynooidea
    - Oxynoidae
    - Volvatellidae
Suborder Notaspidea
- - Superfamily Umbraculoidea
    - Umbraculidae
    - Tylodinidae
Suborder Thecosomata
- Infraorder Euthecosomata
  - Superfamily Limacinoidea
    - Cavoliniidae
    - Limacinidae
- Infraorder Pseudothecosomata
  - Superfamily Cymbulioidea
    - Peraclidae
Order Pulmonata
- Suborder Archaepulmonata
  - - Superfamily Ellobioidea
      - Ellobiidae
Suborder Basommatophora
- - Superfamily Amphiboloidea
    - Amphibolidae
  - Superfamily Siphonarioidea
    - Siphonariidae
    - Trimusculidae

* At this time, only shelled marine mollusks are included in this classification scheme. The other types of mollusks will be added at a later date.

The above material has been adapted from Dr. Rosenberg's The Encyclopedia of Seashells, published by Robert Halt, Ltd., London, 1992.