Sarotherodon linnellii, sometimes known as the unga,[2] blackfin tilapia or blackbelly tilapia, is a cichlid endemic to Lake Barombi Mbo in western Cameroon.

[3] It is critically endangered because of pollution and sedimentation due to human activities.

It is potentially also threatened by large emissions of carbon dioxide (CO2) from the lake's bottom (compare Lake Nyos),[1] although studies indicate that Barombo Mbo lacks excess amounts of this gas.

[4] Juveniles mainly feed on insects (including their larvae) and adults mainly on phytoplankton.

[3] The specific name honours a friend of Lönnberg’s, Gunnar Linnell, a Swede who owned a plantation in Cameroon and who sent a collection of fishes and crustaceans from there which included the type of this fish.