Climbing herb, young branches densely pubescent, becoming glabrous. Leaf trifoliolate, petiole 2-40 cm long, leaflet 4.8-19 cm long, 3.5-16.5 cm broad, obovate, elliptic, rhomboid or ovate, lateral leaflets very oblique, acute or acuminate, pubescent on both sides; petiolule 2-3 mm long; stipules c. 5 mm long. Inflorescence an axillary raceme, 15.0-.30 cm long, flowers single or 2-3 together. Bracts 12.5 mm long; pedicel 2.5-5:O mm long. Calyx 7.5-9 mm long, silky, teeth equal or longer than the tube. Corolla purple. Vexillum 1.5 cm long. Keel 2.5-3.8 cm long, Fruit 5-6.3 cm long, not winged or plaited, with a longitudinal rib running the length of each valve, pubescent, hairs brown and irritating, 5-6- seeded.