Amphilophus citrinellus is a large cichlid fish endemic to the San Juan River and adjacent watersheds in Costa Rica and Nicaragua. In the aquarium trade A. citrinellus is often sold under the trade name of Midas cichlid. A. citrinellus are omnivorous and their diet consists of plant material, molluscs and smaller fish. The species is closely related to, but not to be mistaken for, Amphilophus labiatus, which shares the nickname red devil cichlid.
Midas cichlids are heavily built and are capable of standing up to any other aquarium-sized cichlid in fights over territory. They have powerful jaws, sharp teeth and a physical size advantage in comparison to other aquarium species. Therefore, the aggressivity of Midas cichlids should not be underestimated and cohabitants should be chosen carefully in an aquarium setting.
The conservation status of only one species of this group has been analyzed. The arrow cichlid (Amphilophus zaliosus) was evaluated as Critically Endangered by the IUCN Red List. Among the small body of information regarding populations of the species of this group, four other species may have smaller populations and/or ranges than this fish in Laguna de Apoyo: Amphilophus flaveolus, Amphilophus chancho, Amphilophus supercilius, and Amphilophus globosus. The final member of the complex, Amphilophus astorquii, constitutes about eighty percent of the breeding population of Laguna de Apoyo.
