Idiopoma umbilicata (Lea, 1856) Fig. 5F

Paludina umbilicata Lea, 1856: 109. Type locality: "Takrong River, Siam".

Idiopoma umbilicata: Brandt 1974: 34-35, pl. 2, fig. 35.

Material examined.

ZRC.MOL.015734, ZRC.MOL.015735, ZRC.MOL.015736, ZRC.MOL.015737, ZRC.MOL.015738, ZRC.MOL.015739, ZRC.MOL.015740, ZRC.MOL.015741, ZRC.MOL.015742.

Distribution and habitat.

Tonle Sap Lake and tributaries at Kampong Chhnang, Battambang, Siem Reap and Kampong Thom Provinces, irrigation ponds and paddy fields at Banteay Meanchey and Siem Reap Provinces (locality no. 7, 13, 24, 29 and 39).

Remarks.

Idiopoma umbilicata is often found together with Filopaludina martensi cambodjensis and can be differentiated from the latter species by its smaller size and shouldered shells. It does not appear to be harvested for food.