Slender tree, 2–5 m tall, with characteristically hanging terminal branches and a glaucous foliage; bark smooth, ash grey to white, not flaking; young branchlets purplish-brown, glabrous or pubescent with ± appressed hairs and soon glabrescent. Stipular spines up to 15 mm long, slender, straight. Leaves: pinnae (1–)2–4 pairs; leaflets 4–11 pairs, 2–4.5(–7.5) x 0.8–2(–3) mm, glabrous or sparsely ciliate when young. Flowers pale yellow, in heads 5–5.5 mm in diam.; peduncles 6–15 mm long (up to 25 mm in fruit), with involucel in lower half. Calyx c. 1.2 mm long. Corolla c. 2 mm long, glabrous. Pods straight or curved slightly upwards in upper part, linear-oblong, dehiscent, 3.5–7 x 0.8–1.3 cm, purplish-brown, with oblique veins which converge to become longitudinal in the middle of the valves, sparsely to densely puberulous with appressed hairs. Seeds elliptic to narrowly ovate or almost rhombic in outline, c. 7–8 x 3.5–4 mm; areole central, c. 4.4–4.8 x 1.4–1.6 mm.