Pseudotropheus flavus is a species of cichlid endemic to Lake Malawi where it is only known from Chinyankwazi Island. It prefers areas with rocky substrates where it remains about 1 metre (3.3 ft) above the bottom feeding on plankton. This species can reach a length of 7.6 centimetres (3.0 in) SL. It can also be found in the aquarium trade.