Climbing or straggling bushy shrub 2.5–10 m. high. Stems when young ± densely clothed with short brownish pubescence or puberulence, rarely sparsely clothed or subglabrous, also armed with scattered usually straight spreading prickles up to 8(–10) mm. long. Stipules asymmetrically ovate, acuminate, wavy-margined, 4–20 mm. long, 2–8 mm. wide. Leaves: petiole with rhachis ± 12–47 cm. long, armed with downwardly hooked prickles often in pairs especially at insertions of pinnae; pinnae 4–10 pairs, 2.5–9.8 cm. long; leaflets 8–12 pairs per pinna, elliptic-oblong or slightly obovate, (0.8–)1–2(–2.7) cm. long, 0.3–0.8(–1.7) cm. wide, rounded at apex, pubescent or puberulous on both surfaces. Racemes at ends of main or lateral branches, simple, (10–)16–30 cm. or more long. Bracts very caducous, ovate-triangular to lanceolate, 5–8 mm. long. Pedicels 1.5–2.4(–4) cm. long. Sepals 9–10 mm. long. Petals yellow to yellowish-white, 10–15 mm. long, 8–15 mm. wide (the upper one, however, smaller, ± 8–11 mm. long and 5–6 mm. wide, with margins inflexed in middle). Anthers glabrous. Ovary pubescent. Pod oblong-elliptic, 6–9.5(–12) cm. long (excluding beak), (2–)2.4–2.7(–3.5) cm. wide, straight or slightly curved, compressed, ultimately dehiscent along upper suture, unarmed, shortly pubescent, brown, with a slender beak 0.6–3 cm. long arising near line of upper suture at apex. Seeds ellipsoid, 0.9–1 cm. long, 0.6–0.8 cm. wide, mottled brown and blackish-grey, sometimes all black.
