A genus of tropical shrubs belonging to the legume family (Leguminosae). These plants, with their long branches climbing over other vegetation, occur as members of the jungle undergrowth in Malaysia. Extracts of the roots of Derris elliptica have long been used by the natives as an arrow poison and to stupefy fish so they can be caught more easily. Derris root is an excellent insecticide, being harmful to both chewing and sucking insects, but not poisonous to human beings. The insecticidal ingredient of derris root is a white, crystalline substance, which is called rotenone.