The oscar (Astronotus ocellatus) is a species of fish from the cichlid family known under a variety of common names, including tiger oscar, velvet cichlid, and marble cichlid. 

An ocellatus is native to Brazil, Colombia, Ecuador, Guyana, French Guiana, Suriname, Peru, and Venezuela, and occurs in the Amazon River basin, along the Amazon, Içá, Negro, Solimões, and Ucayali River systems, and also in the Approuague and Oyapock River drainages. In its natural environment, the species typically occurs in slow-moving white-water habitats, and has been observed sheltering under submerged branches.