Tree to 12 m high, crown ± rounded, often irregularly so, branches usually ascenÂding. Bark grey to brownish-black or black, rough, longitudinally fissured; young branch-lets greyish to reddish-brown or purplish, lenticellate, glabrous, smooth, not flaking off to reveal a rusty-red inner layer. Stipules spinescent, in pairs, 0,2-10(14) cm long, straight or slightly curved, sometimes defle-xed, typically stout and slightly swollen, whitish but becoming greyish with age; other prickles absent. Leaves: petiole 0,4-2 cm long, glabrous, eglandular or with a rounded to elliptic gland up to 1,5 x 1 mm, variable in position; rhachis 0-3,6 cm long, glabrous or subglabrous, a small gland at the junction of the top or top 1-3 pinnae pairs; pinnae (1)2-3(5) pairs; rhachillae 0,9-3,6(5,2) cm long, glabrous; leaflets 7-18 pairs per pinna, 3-8 x (1)1,5-2,5(3,2) mm, linear to linear-or obovate-oblong, apex obtuse or rounded, glabrous throughout or rarely margins minutely ciliate, lateral nerves invisible or slightly conspicuous beneath. Inflorescences capitate, on axillary peduncles, fascicled. Flowers white, sessile; peduncles 1,2-2,5 cm long, glabrous or occasionally very sparingly puberulous, eglandular; involucel|-i-way up the peduncle. Calyx glabrous throughout or apices of lobes occasionally with a few hairs, tube 0,8-1,3 mm long, lobes up to 0,3 mm long. Corolla glabrous, tube 1,6-2,2 mm long, lobes up to 0,6 mm long. Stamen-filaments free, up to 5 mm long; anthers with a deciduous apical gland. Ovary up to 1 mm long, glabrous, very shortly stipitate. Pods brown to reddish-brown or purplish, (4,8)6-12,8(15,2) x 0,6-1,1 cm, falcate or occasionally straightish, sometimes irreguÂlarly constricted between some of the seeds, longitudinally dehiscent, valves rather thin, brittle, finely longitudinally veined, glabrous, attenuate basally. Seeds olive-brown, 6-10 x 5-7 mm, ± oblong, smooth, compressed; areole4-6 X 2,5,4-5mm.
