Terrestrial mollusc

However, colonization of the land took place several times during the evolutionary past, and as a result terrestrial molluscs are classified in several different, often not closely related, gastropod taxa.

[2] Terrestrial mollusks comprise about 35 thousand species, most of which belong to the order (in some sources suborder or infraorder) Stylommatophora.

Terrestrial molluscs occur across most of the planet, with the exception of Antarctica and some islands.

[4] According to an estimate from Cameron,[4] of the 409 existing gastropod families, 119 include terrestrial molluscs.

Among these 119 families, 104 are Stylommatophora, 7 are terrestrial pulmonates other than stylommatophorans, and 8 are operculates (formerly "prosobranchs", molluscs with an operculum, a group that primarily consists of marine snails).