Cichlidae

Oscar

Astronotus ocellatus

Orange rimmed eyes guard a thousand eggs

• Black
• Gray
• Orange
• Red
• Tropical
• Regional distribution
• Freshwater fish
• Africa
• Compressed
• Medium
• Tropical fish

Combining imposing muscular girth with expressive facial intelligence, the oscar is a heavy-set freshwater cichlid celebrated throughout the lowland river networks of South America. Its deep, compressed body is covered in an intricate tapestry of dark olive-grey, charcoal, and blazing orange-red blotches that shift into marbling patterns as the fish matures. Near the upper base of the caudal fin sits a prominent, dark ocellus enclosed within a bright orange-red ring, a classic decoy marking that confuses predators approaching from the rear. Indigenous to the Amazon, Orinoco, and Paraná basins across Brazil, Colombia, and Peru, it inhabits slow-flowing river shallows, flooded savannas, and swampy margins down to five meters depth. An opportunistic omnivorous predator, it patrols sunken trees and mud bottoms, feeding on small fishes, river crabs, aquatic insects, and snails. Pairs form long-term monogamous bonds, meticulously polishing flat rocks or logs to lay hundreds of eggs, which both parents aggressively guard against intruders. Maximum recorded total length reaches forty-five centimetres.

Sources: FishBase — Oscar, Astronotus ocellatus