found this:
Flowerhorn, also called Luohan, is a breed of fish. Flowerhorns are thought to arise from the man-made hybridization of a number of cichlid species, from South and Central America. Most notably flowerhorns include Cichlasoma trimaculatum and fishes from the Amphilophus citrinellus (red devil) complex. Flowerhorns first emerged for sale on the aquarium market in Malaysia in the late 1990s. As a probable intergeneric hybrid the fish lacks a specific Latin name. Flowerhorns are, unlike many other hybrids, fertile.
Other notable inclusions in the flowerhorns breeding are Cichlasoma festae and Vieja synspilus ('Redheaded' cichlid). Only the original breeders know exactly which species they crossbred to create the Flowerhorn cichlid. Given the vast amount of mixing, it is doubtful any recorded details of hybridisations exist
says a few species they used for the fh