Terrestrial molluscs

Terrestrial molluscs (mollusks) or land molluscs are ecological group that includes all molluscs that lives on land in contrast to freshwater and marine molluscs.

This group includes land snails and land slugs, however loss of the shell takes place many times in different not evolutionary related groups and in specialized malacological literature land snails and slugs most often viewed together as one group.

All terrestrial molluscs belongs to class Gastropoda, however colonization of land takes place several times during evolution of gastropods, as a result terrestrial molluscs occur in different, often not closely related, gastropod taxa.

Includes about 35 thousands of species, most of them belongs to the order (in some sources suborder or infraorder) Stylommatophora.

Terrestrial molluscs are distributed across almost whole planet except Antarctica and some islands, inhabiting various ecosystems from deserts and tundras to rainforests.

This group is one of the most threatened, there is more known species extinctions of terrestrial molluscs than in any other group of organisms.

According to estimation of Prof. Cameron from the 409 gastropod families there are 119 families that includes terrestrial molluscs, among them 104 are Stylommatophora, 7 are terrestrial pulmonates other than stylommatophorans and 8 are operculates (or formerly "prosobranchs", molluscs with operculum, group that consist mainly marine snails). These groups are probably following:

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