Large, rather erect shrub. Shoots with appressed hairs, strongly compressed. Lvs terete, 40-110 × 1.5-2 mm, initially hairy, becoming glabrous, simple or pinnate with 2-7 terete pinnae (different forms on the same plant), rigid and spiny. Fls up to c. 50 in dense short racemes. Rachis villous, c. 1.5 cm long. Pedicels 3-5 mm long, glabrous. Perianth white, glabrous, < pedicels. Ovary sessile, glabrous; style glabrous; stigma cone erect, symmetric. Fr. 2-2.5 × 1.6-2 cm, pale brown, slightly to moderately rugose; beak very short, incurved. Seed 17-20 × c. 6 mm (including wing), black; wing extending down 1 side.