Red List Category
for more information about the Red List categories and criteria
Justification of Red List category
Thorough surveys of Lake Alaotra in 1989, and further surveys in 2004 and 2009 failed to find any evidence of the species. Considering the last confirmed sighting of the species was in 1982, and in view of the threats to the species, its lack of mobility and restricted range, this species is now considered to be Extinct.
Land-mass type - shelf island - Continental islands include all other islands or island groups. Generally they were once part of continents and lie on a continental shelf of < 200 m sea depth.
Realm - Afrotropical - realm
IUCN Ecosystem -- Freshwater biome