マメ科ササゲ属の一年草で、学名は Vigna angularis var. nipponensis。英名はありません。
The "Yabu-tsuru-azuki" (Vigna angularis var. nipponensis) belongs to Fabaceae (the Pea family). It is an annual herb that is native to Honshu, Shikoku and Kyushu of Japan, as well as Taiwan, the Korean Peninsula and China. This herb grows in grasslands of mountains and fields, and spreads by trailing vines. The leaves are trifoliate. The leaflets are narrow-ovate to ovate with acute tips and sometimes trilobate. The yellow papilionacenous flowers come in August to October. The fruits are seed pods and linear 4-9 cm long. the Azuki bean is said to be made improvements from this spices. It is called "野紅豆" in Taiwanese Chinese and "赤豆" (chi dou) in Chinese.