Stem 1.2-1.5 m tall, slightly striate, glabrous. Stipules 9-20 mm long, scarious, very acute. Leaves unifoliolate; petioles 3-10 mm long, leaflets 5-15.0 cm long, 0.9-1.9 cm broad, oblong or lanceolate, obtuse or subacute, base subcordate, glabrous above, appressly hairy on the nerves beneath; petiolules very short, stipels linear, acute. Inflorescence dense spicate raceme, 15-30 cm long. Bracts often longer than 1.3 cm, ovate, acuminate, silky outside, caducous. Pedicel c. 2.5 mm long. Calyx 6-16 mm long, striate, pubescent, teeth longer than the tube. Pods 0.9-1.3 cm long, 2-2.5 mm broad, shortly stalked, slightly moniliform, terete-compressed, 4-6 jointed, minutely pubescent, reticulately veined, veins not obscure.