Common name: Cuban cichlid
Scientific name: Nandopsis tetracanthus
Origin: Central America: endemic to Cuba, but specimens have also been collected from Barbados, Haiti and the Dominican Republic. 
Size: Potentially as large as 20cm/8", with typical females being around 13cm/5" and males a touch bigger. 
Water: Unusually for a cichlid this fish is found in both freshwater and brackish areas. However, there is no need to add salt and I've kept this species in hard, alkaline freshwater for years without problems.
Diet: Stomach analyses of wild fish have shown that they feed on shrimps, worms, aquatic insects and small fishes, including livebearers and gobies. Aquarium specimens do well on good quality cichlid pellets, whole shrimp and earthworms.