Apistogramma is a genus of approximately a hundred species of fish from the family Cichlidae. They are found east of the Andes in tropical and subtropical South America, ranging as far south as northern Argentina. The greatest species richness is in the Amazon Basin. Apistogramma literally means "irregular lateral line" referring to a common trait of the species under this taxon. Most species are strongly sexually dimorphic, with males generally larger (up to 7 to 9 cm) and differently coloured to females. But in a few species this pattern is reverse. All Apistogramma species are micropredators. Their main prey items consist of fry of other fish, insect larvae and other invertebrates. Apistogramma species are popular aquarium residents, particularly in community or planted aquariums.