"Ezono-ryukinka" (Caltha palustris var. barthei) belongs to Ranunculaceae (the Buttercup family). It is a perennial herb that is distributed from northern Honshu to Hokkaido in Japan, as well as the Kuril Islands, Sakhalin, and East Asia. It grows along the margins of streams in the subalpine to alpine zones and grows 50 to 80 cm tall. The leaves are larger than the "Marsh marigold" and have triangular serrations on the edges. From July to early August, the flower stalks extend to produce bright yellow flowers. There are no petals, but sepals that look like petals. The Chinese name is "空茎驢蹄草" (kong jing lu ti cao).