The Antarctic toothfish (Dissostichus mawsoni), also known as the Antarctic cod, is a large, black or brown fish found in very cold (subzero) waters of the Southern Ocean near Antarctica. It is the largest fish in the Southern Ocean, feeding on shrimp and smaller fish, and preyed on by whales, orcas, and seals. It is caught for food and marketed as Chilean sea bass together with its sister species, the more northerly Patagonian toothfish (D. eliginoides). Often mistakenly called "Antarctic cod", the Antarctic toothfish belongs to the notothen family (Nototheniidae), a family of fish genera that are abundant near Antarctica.