The wild-type of the species has 8–9 black vertical bars on a blue-grey body, along with a dark blotch on the
operculum.
[1] Juvenile convict cichlids are
monomorphic until they reach
sexual maturity. Unusually for fish, the female is more highly coloured.
[14] The male is mostly gray with light black stripes along the body. Males are larger than females, and they have more pointed
ventral,
dorsal and
anal fins which often extend into filaments. In addition, older males frequently develop
vestigial fatty lumps on their foreheads. She has more intense black bands across the body, and pink to orange colouration in the ventral region and on the dorsal fin.
[15][16] The average
standard length of mature males in the wild ranged from 6.3–6.6 centimeters, while breeding–sized females ranged from 4.2–5.5 centimeters.
[14] The maximum standard length has been reported to be 10 centimeters, with total length near 12 centimeters (4.7 in).
[1][17] Body weight has been reported to range from 34–36 grams (1.2–1.3 oz).
[1] Selective breeding has resulted in a
leucistic strain of convict cichlids, in which the dark barring of the wild type is absent.
[15] These are also known as
white convicts,
pink convicts,
gold convicts and
A. nigrofasciata "Kongo",.
[1][16] The leucistic colouration is caused by a
mutation in an
autosomal gene and is
recessively inherited.
[18]