Pseudotropheus crabro

Pseudotropheus crabro, the bumblebee cichlid or hornet cichlid, is a freshwater fish of the cichlid family found only in Lake Malawi, where it lives in a range of habitats but is most often seen in large caves or near big boulders. It is a fairly small fish, reaching about 16 centimetres in standard length, with an elongate body marked by vertical yellow and black bars that give it the bumblebee name. Young fish are brightly coloured and darken as they mature, especially the males, and the species is known for changing its colours rapidly. Like many Lake Malawi cichlids it is a mouthbrooder. In the wild it is a specialised feeder that acts as a cleaner fish for the large catfish Bagrus meridionalis, called the kampango, eating the fish lice Argulus africanus and dead tissue from the catfish, and it also raids the catfish's nests for eggs, turning dark brown while it does so. It is kept in aquariums as a hardy and very aggressive mbuna, usually one male with several females.