The stone flounder, Kareius bicoloratus, is a flatfish of the family Pleuronectidae. It is a demersal fish that lives on sandy and muddy bottoms in coastal areas at depths of up to 150 metres (490 ft). Its native habitat is the temperate waters of the northwest Pacific, from Japan to the Kuril islands, Sakhalin, Korea, northern China and ******. It is oceanodromous and is found in salt, brackish and fresh waters. It can grow up to 50 centimetres (20 in) in length, and may reach 12 years of age.