Astronotus

Astronotus is a genus of freshwater fish, family Cichlidae, order Cichliformes, native to South America and comprising three recognized species, though genetic evidence suggests further undescribed species may exist. Astronotus ocellatus and Astronotus crassipinnis occur in the Amazon Basin, with Astronotus crassipinnis additionally found in the Parana and Paraguay river systems, while Astronotus mikoljii inhabits the Orinoco River and Gulf of Paria basins of Venezuela and Colombia. Members of the genus grow to about 35 centimeters, show no visible difference in appearance between sexes, and are opportunistic omnivores that eat fish, fruit, nuts, crustaceans, mollusks and other invertebrates. Juveniles display coloration distinct from adults, likely aiding camouflage. The oscar, Astronotus ocellatus, forms monogamous breeding pairs that spawn on flattened stones in open areas and is widely kept in the aquarium trade, unlike Astronotus crassipinnis, which is seldom exported for that purpose.