Milne Edwards, 1848
Gastropods displaying torsion, with marked subsequent modification of the anterior mantle cavity. Respiration conducted via single (primitively paired) gill within the mantle cavity. Head with pronounced snout, tentacles, and eyes. Shell typically coiled, often massively developed. Feeding and reproductive modes highly varied. Mostly marine, occuring abundantly from the supralittoral to the abyss. Most primitive group of the gastropods, from which the other types, the opisthobranchs and pulmonates have been derived.
Source: Hayward et al., 1990; Graham, 1988.
The following subtaxa of this subclass occur in the region:
Superorder Archaeogastropoda
Superorder Caenogastropoda
Order Docoglossa
Order Neogastropoda
Order Neotaenioglossa
Order Vetigastropoda
Suborder Ptenoglossa
Superfamily Scissurelloidea
Family Aclididae
Family Acmaeidae
Family Adeorbidae
Family Aporrhaiidae
Family Assimineidae
Family Barleeidae
Family Buccinidae
Family Caecidae
Family Calyptraeidae
Family Capulidae
Family Cerithiidae
Family Cerithiopsidae
Family Epitoniidae
Family Eratoidae
Family Eulimidae
Family Fissurellidae
Family Haliotidae
Family Hydrobiidae
Family Iravadiidae
Family Lacunidae
Family Lamellariidae
Family Lepetidae
Family Littorinidae
Family Lottiidae
Family Muricidae
Family Nassariidae
Family Naticidae
Family Neritidae
Family Ovulidae
Family Patellidae
Family Ranellidae
Family Rissoidae
Family Scissurellidae
Family Skeneidae
Family Skeneopsidae
Family Tornidae
Family Tricoliidae
Family Triphoridae
Family Triviidae
Family Trochidae
Family Turridae
Family Turritellidae
Family Velutinidae
Genus Aclis
Genus Acmaea
Genus Alvania
Genus Amauropsis
Genus Anatoma
Genus Ansates
Genus Aporrhais
Genus Assiminea
Genus Barleeia
Genus Bela
Genus Beringius
Genus Bittium
Genus Buccinum
Genus Caecum
Genus Calliostoma
Genus Calyptraea
Genus Capulus
Genus Cerithiella
Genus Cerithiopsis
Genus Charonia
Genus Cheirodonta
Genus Cingula
Genus Circulus
Genus Clelandella
Genus Colus
Genus Comarmondia
Genus Crepidula
Genus Crisilla
Genus Dikoleps
Genus Diodora
Genus Emarginula
Genus Epitonium
Genus Erato
Genus Eulima
Genus Euspira
Genus Gibbula
Genus Haliella
Genus Haliotis
Genus Hyala
Genus Hydrobia
Genus Iothia
Genus Jujubinus
Genus Lacuna
Genus Lamellaria
Genus Lepeta
Genus Liomesus
Genus Littorina
Genus Mangelia
Genus Manzonia
Genus Margarites
Genus Marshallora
Genus Melanella
Genus Melaraphe
Genus Mercuria
Genus Nassarius
Genus Neptunea
Genus Nucella
Genus Obtusella
Genus Ocenebra
Genus Oenopota
Genus Onoba
Genus Osilinus
Genus Patella
Genus Pelseneeria
Genus Potamopyrgus
Genus Propilidium
Genus Puncturella
Genus Pusillina
Genus Raphitoma
Genus Semisalsa
Genus Simnia
Genus Skenea
Genus Skeneopsis
Genus Tectura
Genus Teretia
Genus Theodoxus
Genus Tornus
Genus Trichotropis
Genus Tricolia
Genus Trivia
Genus Trophon
Genus Troschelia
Genus Turritella
Genus Typhlomangelia
Genus Urosalpinx
Genus Velutina
Genus Ventrosia
Genus Vitreolina
Genus Volutopsius
Aclis minor
Aclis walleri
Acmaea virginea
Alvania abyssicola
Alvania beani
Alvania cimicoides
Alvania jeffreysi
Alvania lactea
Alvania punctura
Alvania subsoluta
Amauropsis islandica
Anatoma crispata
Ansates pellucida
Aporrhais pespelecani
Aporrhais serresianus
Assiminea grayana
Barleeia unifasciata
Bela brachystoma
Bela nebula
Beringius turtoni
Bittium reticulatum
Buccinum humphreysianum
Buccinum hydrophanum
Buccinum undatum
Caecum clarkii
Caecum glabrum
Caecum trachea
Calliostoma occidentale
Calliostoma zizyphinum
Calyptraea chinensis
Capulus ungaricus
Cerithiella metula
Cerithiopsis tubercularis
Charonia lampas
Cheirodonta pallescens
Cingula trifasciata
Circulus striatus
Clelandella miliaris
Colus gracilis
Colus islandicus
Colus jeffreysianus
Comarmondia gracilis
Crepidula fornicata
Crisilla semistriata
Dikoleps pusilla
Diodora graeca
Emarginula crassa
Emarginula fissura
Emarginula rosea
Epitonium clathratulum
Epitonium clathrus
Epitonium trevelyanum
Epitonium turtonis
Erato voluta
Eulima bilineata
Eulima glabra
Euspira catena
Euspira fusca
Euspira montagui
Euspira pallida
Euspira pulchella
Gibbula cineraria
Gibbula magus
Gibbula pennanti
Gibbula tumida
Gibbula umbilicalis
Haliella stenostoma
Haliotis tuberculata
Hyala vitrea
Hydrobia neglecta
Hydrobia ulvae
Iothia fulva
Jujubinus exasperatus
Jujubinus montagui
Jujubinus striatus
Lacuna crassior
Lacuna pallidula
Lacuna parva
Lacuna vincta
Lamellaria latens
Lamellaria perspicua
Lepeta caeca
Liomesus ovum
Littorina arcana
Littorina fabalis
Littorina littorea
Littorina neglecta
Littorina nigrolineata
Littorina obtusata
Littorina saxatilis
Mangelia attenuata
Mangelia coarctata
Mangelia smithii
Manzonia crassa
Margarites groenlandicus
Margarites helicinus
Marshallora adversa
Melanella alba
Melanella lubrica
Melanella monterosatoi
Melaraphe neritoides
Mercuria confusa
Nassarius incrassatus
Nassarius nitidus
Nassarius pygmaeus
Nassarius reticulatus
Neptunea antiqua
Neptunea contraria
Nucella lapillus
Obtusella intersecta
Ocenebra erinacea
Oenopota rufa
Oenopota trevelliana
Oenopota turricula
Onoba aculea
Onoba semicostata
Osilinus lineatus
Patella intermedia
Patella ulyssiponensis
Patella vulgata
Pelseneeria minor
Potamopyrgus antipodarum
Propilidium exiguum
Puncturella noachina
Pusillina inconspicua
Pusillina sarsii
Raphitoma leufroyi
Raphitoma linearis
Raphitoma purpurea
Rissoa lilacina
Rissoa membranacea
Rissoa parva
Rissoa porifera
Semisalsa stagnorum
Simnia patula
Skenea serpuloides
Skeneopsis planorbis
Tectura testudinalis
Teretia teres
Theodoxus fluviatilis
Tornus subcarinatus
Trichotropis borealis
Tricolia picta
Trivia arctica
Trivia monacha
Trophon barvicensis
Trophon clathratus
Trophon muricatus
Trophon truncatus
Troschelia berniciensis
Turritella communis
Typhlomangelia nivalis
Urosalpinx cinerea
Velutina plicatilis
Velutina velutina
Ventrosia ventrosa
Vitreolina philippi
Volutopsius norwegicus