The Remo flounder, Oncopterus darwinii, is an edible flatfish of the monotypic family Oncopteridae. It is a demersal fish that lives on bottoms at depths of between 20 and. Its native habitat is the southwestern Atlantic along the southeast coast of South America, from Santa Catarina, Brazil in the north to the San Matías Gulf, Argentina in the south. It can reach 30 cm in length.

Identification: The Remo flounder is "righteyed", with both its eyes on the right-hand side of its body. Its upper surface is pale brown in colour with small white spots, and large white spots at its edges. The lateral line is marked by a distinctive semi-circular curve above the pectoral fin.