A small or medium sized tree, up to 15 m tall, deciduous; dark grey or greyish brown bark peeling off in long strips or in narrow rectangular plates, brown and red inside. Young branches puberulous. Leaf bipinnate compound; stipules spiny, flattened, hooked and pointed, up to 8 mm long; rachis c. 7-17 cm long, pilose, with a large gland near the base of the petiole and often several small glands between the pinnae; pinnae 10-30 pairs, c. 1.3-3.5 cm long, pilose; leaflets 16-50 pairs, c. 3-6 mm long, petiolule 1 mm long, base oblique, linear, tip obtuse to subacute, glabrous or pubescent, nerves obscure. Inflorescence 1-4-nate axillary pedunculate spike, 2.5-10 cm long; peduncle c. 1.2-1.8 cm long. Calyx c. 1.2-1.5 mm long, campanulate, pubescent or villous outside, teeth deltoid. Corolla c. 2.4-3.1 mm long, villous or slightly pubescent, lobes ovate, oblong, subacute. Pod 5.0-8.7 cm long, c. 1.0-1.5 cm broad, flat, thin brown, shining, narrowed at the base into a c. 3-7 mm long stalk, triangular beaked at the apex, dehiscent. Seeds 3-10 per fruit.