Derris is a genus of approximately 65 flowering plants in the legume family Fabaceae, order Fabales. The genus comprises woody vines and shrubs distributed across a broad tropical and subtropical range, from eastern Africa through the Indian subcontinent and Southeast Asia to New Guinea, northern Australia, and the southwest Pacific islands.
Members of Derris are best known for their chemical properties. The roots of Derris elliptica, one of the most studied species, are rich in rotenone — a naturally occurring compound that acts as a potent insecticide and fish poison. This property has made extracts of the genus significant in both traditional and commercial pest control. Despite these defensive secondary compounds, several Derris species serve as larval food plants for Lepidoptera, including moths in the genus Batrachedra.
The genus belongs to the tribe Millettieae within Fabaceae and shares the characteristic legume pod fruit of that family. Most species are climbing plants or lianas adapted to forest margins and disturbed woodland habitats across the Asian tropics.
Distribution
Derris ranges from eastern Africa across the Indian subcontinent and Southeast Asia to New Guinea, northern Australia, and the southwest Pacific islands. The genus is predominantly tropical, with most species occurring in humid forest and forest-edge habitats.
Ecology
Derris species are woody climbers and lianas of tropical forest margins. Despite producing rotenone and other secondary metabolites as apparent defenses, they support populations of Lepidopteran larvae — including Batrachedra species — as larval host plants.
Cultural Uses
Derris roots, particularly those of Derris elliptica, have long been used by indigenous communities across Southeast Asia as a fish poison (rotenone disrupts cellular respiration in aquatic animals). The same compound was widely adopted as a botanical insecticide in agriculture during the 20th century, valued for its relatively rapid environmental breakdown compared with synthetic alternatives.
