Changes

*Deciduous shrub or small tree up to 6(–12) m tall; bole often irregular and low-branching, up to 25 cm in diameter; bark surface nearly smooth to rough or deeply fissured, dark grey to greyish brown, peeling off in strips, inner bark thick, fibrous, yellowish white; crown open, with spreading branches; lateral twigs with sharp spines at apex, short-hairy. *Leaves alternate, bipinnately compound with (2–)5–19(–21) pairs of pinnae; stipules small; petiole and rachis together up to 20 cm long, with a stalked gland between pairs of pinnae; leaflets in 9–41 pairs per pinna, sessile, oblong to linear, up to 1 cm × 0.5 cm, glabrous to slightly hairy. *Inflorescence an axillary long-stalked spike 1–12 cm long, pendent, slightly hairy. *Flowers sterile and pinkish in lower part of inflorescence, bisexual and yellow in upper part of inflorescence, regular, 5-merous; calyx 0.5–1 mm long, with slightly hairy tube and short lobes; corolla lobes 1.5–3 mm long, slightly fused at base, glabrous; stamens 10, 3–5 mm long, with gland on top of anthers, much longer but without anthers in sterile flowers; ovary superior, ellipsoid, c. 1 mm long, slightly hairy, 1-celled, style slender. *Fruit a narrowly oblong flattened pod, 2–10 cm × 0.5–2.5 cm, becoming contorted or spiral, leathery, glabrous, dark brown, indehiscent or irregularly opening, c. 5-seeded. *Seeds flattened ellipsoid, 4–6 mm × 3–4.5 mm, glossy brown.