Alisma canaliculatum
Alisma canaliculatum, commonly known as channelled water plantain, is a species of plants in the Alismataceae. It is native to Japan, Korea, the Ryukyu Islands, Taiwan, the Kuril Islands, and China.
Alisma canaliculatum is a perennial herb with tubers up to 3 cm across. Leaves are lanceolate, up to 50 cm long. Flowers are white, borne in a branching panicle.