Tree 2·5-15 m. high, flat-crowned; bark green, peeling or scaling; young branchlets pubescent to sometimes subglabrous, with numerous reddish sessile glands; twigs grey, brown or plum-coloured, not showing yellow bark. Stipules spinescent, varying in length, up to 8 cm. long, straight or almost so; “ant-galls” and other prickles absent. Leaves: rhachis 3-8 cm. long, normally rather densely pubescent above; pinnae 6-14 pairs (some leaves always with 8-9 pairs or more); leaflets numerous, small, 2-5 x 0·5-1(1·25) mm., narrowly oblong or oblong-linear. Flowers with red corolla and white stamen-filaments, in axillary heads whose involucels are conspicuous, 2-3 mm. long and near the base of or 1/5-1/2-way up the peduncle; peduncles rather densely pubescent and with sessile glands throughout, rarely sparingly pubescent. Pods indehiscent, 3·5-9 x 0·8-2·1(2·5) cm., narrowly oblong, straight (or bent only in a plane at right-angles to the flattened plane of the pod), often ± moniliform with the segments mostly as wide as or wider than long; in our area each segment with a medium or small wart-like projection up to 4·5 mm. high in the centre of each of its flat sides. Seeds blackish-olive, 5-7 x 4·5-5·5 mm., smooth, subcircular to elliptic, compressed; areole 3·5-5 x 2·5-3 mm.