Beddomeia tumida is a tiny (3-4 mm) freshwater snail known to occur only in the Great Lake, in north-central Tasmania. The species has a very restricted range, recorded from only six areas across the lake. The principal threats to B. tumida are associated with impoundment management, agricultural clearing and forestry. B. tumida may also be impacted by competition with and displacement by the exotic snail Potamopyrgus antipodarum (New Zealand hydrobiid). The principal management objectives for B. tumida include preventing the loss or degradation of habitat supporting known populations, and increasing public awareness of the species.