Nannacara (Golden Eye Cichlid) is a genus of small freshwater cichlid fish endemic to South America. The genus is part of the Cichlasomatini tribe of the Cichlasomatinae subfamily. In the aquarium hobby, the fish is considered a dwarf cichlid along with Apistogramma, Mikrogeophagus, and Dicrossus species. Nannacara anomala is the most commonly encountered species in the aquarium trade.
The male, under acidic conditions, adopts a greenish tinge along the length of its body, while the female puts on a black coat with a faint line running from her face to the middle of her tail, and in breeding condition, fades into a bright yellow in the stomach.
As youngsters, there is hardly any difference as a juvenile male does have the colouration of a female. The only difference would be the presence of an extension at the back of the male's dorsal fin.