Perennial climber or trailer, up to several m long. Leaflets elliptic, oblong-elliptic to subcircular, 2.5–9.5(–11.5) x 1.5–9(–10) cm, obtuse or emarginate but sometimes minutely apiculate at the apex, glabrous to pubescent on both surfaces. Calyx-tube 7–9 mm long; upper lip 4–5 mm long. Corolla pink, purple or bluish-mauve, 2.5–3 cm long. Pod linear-oblong, 11.5–16 x 2.5–2.9 cm, with longitudinal ribs close to the upper margin. Seeds 1.5–2 cm long, brown to almost black; hilum 7–8.5(–10) mm long.