Seema, also sima an sema (Russian сима, Japanese サクラマス or ヤマメ), Japanese salmon, Masu salmon, or cherry salmon, Oncorhynchus masou, is a salmon of the western Pacific Ocean: (Kamchatka, Kuril Islands, Sakhalin, Primorsky Krai, Korea, Japan). A landlocked subspecies commonly called the Taiwanese salmon or Formosan salmon (Oncorhynchus masou formosanum) also exists in Taiwan.