Barombi Mbo Crater Lake. 08/10/06; South-West province; 415 ha; 04°40'N 009°23'E. A deep volcanic crater lake, the site forms with three other crater lakes in the Southwest Province of Cameroon the so-called "Afrotropical Cameroon Crater Lakes Ecoregion". It is famous among biologists for the occurrence of 12 endemic fish-species, rendering it one of the places with the highest densities of endemic species per area in the world. For evolutionary biologists, the lake represents one of the few examples where new species have evolved within the confines of a small area by "sympatric speciation ". Lake Barombi Mbo is also important due to the presence of freshwater sponges, one of which (Corvospongilla thysi) is also endemic. It is an important sacred site to the Barombi tribe: the social and cultural life of the Barombi Mbo People is intimately linked to the use of the resources of the lake through fishing, mythology and transport, and to the surrounding land through farming. It is also a source of clean water for the metropolis of Kumba and its environs. Over-fishing, introduction of foreign fish to the ecosystem, pesticide spraying of cocoa-trees within the catchment area and deforestation on the crater rim are the main (potential and actual) threats to the site. The elaboration and implementation of a management plan needs to occur. Ramsar site no. 1643. Most recent RIS information: 2006.