Just to point out at this juncture, many of the fishes previously placed in the Genus
Tilapia have since been relocated to other Genera, such as
Sarotherodon. There's also a brace of Genera among the African Cichlids that contain -tilapia as a suffix, such as
Chromidotilapia,
Astatotilapia,
Chilotilapia,
Coelotilapia,
Cynotilapia,
Cyphotilapia (the species
Cyphotilapia frontosa is an expensive aquarium fish costing $200 a pop in the US),
Hemitilapia,
Heterotilapia,
Limnotilapia,
Paratilapia,
Petrotilapia (the species
Petrotilapia tridentiger is a beautiful purple coloured aquarium fish, but one with a
vicious temperament), and
Xenotilapia.
There's also a brace of relations such as
Alcolapia alcalicus, which lives in the waters of Lake Natron, an environment most people would consider to be completely inimical to fish life, given that the water of this lake is as as alkaline as a household ammonia solution, and has a dissolved content of sodium carbonate that would kill most other fish.
Here's an image of the nice purple
Petrotilapia tridentiger:
The woefully expensive
Cyphotilapia frontosa looks like this:
The Dogtooth Cichlid,
Cynotilapia afra, looks like this:
And the hilariously named "Eastern Happy",
Astatotilapia calliptera, looks like this:
For those who like variety among their fish, the Cichlidae contains something like 2,500 species, of which 1,700 or more are African, and 1,400 or so known from the Rift Lakes.