Description from Flora of China
Shrubs, erect. Young branchlets trigonous-prismatic. Leaves digitately 3-foliolate; stipules lanceolate, 1-3 cm, apex acuminate, deciduous; petiole 3-10 cm, robust, narrowly winged or not, pubescent; petiolules 3-6 mm, densely reddish pubescent; leaflets papery to thickly papery, with dense dark brown glands; terminal leaflet elliptic or elliptic-lanceolate, rarely obovate, 8-14 × 4-6(-8.5) cm, pubescent, basal veins 3, base broadly cuneate or rounded, apex acuminate or acute; lateral leaflets oblique, broadly lanceolate, base rounded at one side, other narrowly cuneate. Raceme terminal or 1-3 per axil, 3-11 cm, densely rusty villous; bracts elliptic or elliptic-lanceolate, 0.7-1 cm, exterior densely rusty villous, apex usually obtuse; peduncle ca. 2 mm. Flowers 1-1.2 cm, clustered. Calyx ca. 10 mm; lobes 4-7 mm, lower one longest. Corolla purple or pink, longer than calyx; standard obovate or obovate-elliptic, auricles obtuse; wings oblong to obovate-oblong, slightly curved, with long slender claw, auricle decurrent; keel semiorbicular, wider than wings, clawed, with acute auricle. Ovary elliptic, with very pale brown hairs; style slender. Legume elliptic, 12-15 × 7-8 mm, rusty villous, inflated, apex with acute beak. Seeds 2, black, suborbicular, ca. 2 mm in diam. Fl. and fr. almost year-round.
Fields, mountain slopes, forests; 500-2100(-2700) m. Guangxi, Hainan, ?Sichuan, Yunnan [Cambodia, India, Laos, Myanmar, Vietnam].