Oncorhynchus kawamurae

Black kokanee (Oncorhynchus kawamurae), or kunimasu (国鱒; "[Japanese] national trout") in Japanese, is a species of landlocked Pacific trout in Japan that was thought to be extinct for 70 years before being rediscovered in 2010. The species was originally endemic to Lake Tazawa, Akita Prefecture, but was translocated to Lake Saiko in an attempt to save the species. These efforts were only discovered to have been successful in 2010 when nine specimens were captured by a team of researchers including a celebrity biologist, 'Sakana-kun'.

Oncorhynchus kawamurae is related to the sockeye salmon (Oncorhynchus nerka) and has been earlier treated as its subspecies O. nerka kawamurae. The fish is dark olive with black spots on its back, and grows to approximately one foot (30 centimetres) in length. This species has a long, slim and flat body shape but experiences changes in color and shape depending on the sex and life stage. Kunimasu also has a distinct breeding season, fewer pyloric caeca, and more gill-rakers which distinguish it from Oncorhynchus nerka.