Perennial climber. Stem twining, setose. Stipules 10-12 mm long, free lateral, setose. Leaf pinnately trifoliolate, petiole 5-30 cm long, pilose. Stipels 8 mm long, setose, petiolule 5-8 mm long, pilose, lamina 7.5-21 cm long, 7.5-20.0 cm broad, broadly ovate to trilobed, tip acute, pubescent on both sides. Inflorescence an axillary, peduncled raceme, 15-32 cm long, velutinous, peduncle 2-3 cm long. Bracts c. 3 mm long, pilose to setose. Pedicel c. 7 mm long, pilose. Calyx 10-14 mm long, setose, teeth unequal, longest 7-12 mm long. Corolla purple with yellow spot at the base of the standard. Vexillum c. 15-18 cm long. Fruit c. 2.5-6.0 cm long, 7-8 mm broad, hispid, hairs brown.