Persicaria filiformis

Persicaria filiformis is a species of flowering plant in the family Polygonaceae, native to the Kuril Islands, Japan (including the Ryukyu Islands), Korea, Myanmar, the Philippines and Vietnam. It was first described as "Polygonum filiforme" in 1784 by Carl Thunberg and transferred to the genus "Persicaria" in 1819 by Takenoshin Nakai. The species has been treated as the variety "filiformis" of "Persicaria virginiana", a North American species.