Tomichia cawstoni is a species of very small freshwater snails which have a gill and an operculum, gastropod molluscs or micromolluscs in the family Tomichiidae.

[1] The type locality is Kokstad, KwaZulu-Natal, Eastern Cape Province, South Africa.

[2] The natural habitat for this species is rivers in riverine forests, predominantly of freshwater in contrast to other species which inhabit ephemeral streams and rivers.

[1][3] Species of the genus Tomichia are particularly susceptible to changes in their ecosystem, and thus species such as Tomichia cawstoni are greatly threatened by pollution and climatic changes (especially in the form of changes in rain cycles).

In Kokstad, it is threatened by pollution and trampling from commercial cattle farming operations.