Sarotherodon linnellii, sometimes known as the unga, Blackfin tilapia or Blackbelly tilapia, is a of cichlid endemic to Lake Barombi Mbo in western Cameroon. This species reaches a length of 18.5 centimetres (7.3 in) SL. It is threatened because of pollution and sedimentation due to human activities, and potentially also by large emissions of carbon dioxide (CO2) from the lake's bottom (compare Lake Nyos).