The Karstveld sinkhole lakes and caves are distinctive subterranean habitats, supporting a substantial number of endemic aquatic species within several taxonomic groups. The Karstveld is the name given to extensive dolomite and limestone formations located to the southeast and east of the Etosha Pan in Namibia. The area covers the Otavi Mountains and continues westward through the northern parts of Outjo District as far as Otjovasandu (Irish 1992).