キンポウゲ科キンポウゲ属の多年草で、学名は Ranunculus japonicus。英名は Mao gen。
The Mao gen (Ranunculus japonicus) belongs to Ranunculaceae (the Buttercup family). It is a perennial herb that distributed in Japan, from Tohoku region of Honshu west to Shikoku and Kyushu in Japan, as well as the Korean Peninsula, Taiwan and China. This herb grows in sunny fields and mountains, and up to a height of 30-70 cm. The basal leaves are divided into 3-5 lobes palmately with long petioles. The yellow, glossy flowers bloom atop of the stem from March to May. The whole plant contains toxic protoanemonin and ranacrine. The Japanese name is derived from the shape of basal leaf resembles the hooves of the horse. Both the Taiwan Chinese and Chinese names are "毛茛" (mao gen).