"Siinoki-kazura" (Derris trifoliata) belongs to Fabaceae (the Pea family). It is an evergreen woody vine that is distributed to the Ryukyu Islands in Japan, as well as Taiwan, southern China, the tropical Asia and the Polynesia. This vine grows in mangrove edges and coastal secondary forests, entwines itself around adjascent trees, and can reach 10-15 m long. The leaves are impari-pinnate compound with 3-9 ovate-oblong leaflets. They are leathery and glossyish. The racemes are borne at the axils and white labiate flowers bloom from June to August. The fruits are broad elliptic seed pods.