Astronotus ocellatus is a species of fish from the cichlid family known under a variety of common names including oscar, tiger oscar, velvet cichlid, or marble cichlid. In South America, where the species naturally resides, A. ocellatus specimens are often found for sale as a food fish in the local markets.The fish introduced to other areas, including China, Australia, and the United States. It is considered a popular aquarium fish in the U.S. Wikipedia