Pseudotropheus johannii Eccles, 1973, a mbuna cichlid from Lake Malawi,
has been traditionally included in genus Melanochromis based on similarities of
the melanic coloration pattern. These similarities are due to convergent
evolution rather than close affinities, as attested by some characteristics
exposed in this paper. New criteria towards increased precision of the
definition of genus Melanochromis are additionally proposed.
[English abstract as given in the article]