I know of atleast 2 of them. Hemichromis elongatus and hemichromis frempongi. Frempongi being more rare than the elongatus. If you've never kept these fish before or you're new to the cichlid seen, I wouldn't reccomend this as your first fish. They are super aggressive and with time, will kill each other off until there is one. If you get them to pair, nothing else would be able to live in the tank. I read this ad of a guy trying to sell a breeding pair of frempongi's, he said, at 6 inches they killed two 12 inch oscars, one 10 inch red devil and a pair of breeding Jack Dempsey's. If your ready for something like this, I would say go for it. Elongatus and frempongi's have been my favorite cichlids for about 10 yrs. Not for their fighting, their personalities are awsome to watch.