Small to medium-sized tree, 10-15 (-20) m tall, 20-40 cm bole diameter, typically branchy when young, older trees with a short clear bole to 3-5 m, upright angular branch ing, and a spreading, open crown. Bark on young branches smooth, mid-grey or grey brown, inner bark cinnamon brown then pale salmon pink, on older branches and bole darker grey-brown and rougher with shallow rusty orange-brown vertical fissures (Fig. 3A). Shoots terete, slightly striate, mid-orange-brown, puberulent. Stipules 3.2-4 mm long, ovate or lanceolate, with asymmetric membranous wings at base, venation and midrib prominent, caducous. Leaves (7-) 14-20 (-23) cm long, (3-) 5-13 cm wide; petioles (including swollen green or slightly blackened pulvinus) (11-) 14-28 mm long, sparsely puberulent, with a single yellow-green or green, sessile, rounded, elliptic, dome-shaped or truncate-conic nectary with a narrow central pore (Fig. 9C), 2 x 1 mm, at the distal end on adaxial side of petiole; rachis 3.7-17 cm long, sparsely pubescent, sometimes with a small elliptic conic nectary at the distal end, apex of rachis extending beyond the terminal pinnae as a pointed dark brown mucro (1-) 1.5-2.8 mm long, curling when dry; pinnae (5-) 6-16 pairs; pinnular rachis (3.7-) 4-8.7 cm long, angled, puberulent, with 1 or 2 minute elliptic nectaries at base of terminal pairs of leaflets; leaflets 25-56 pairs per pinna, 3.7-7 mm long, 1-1.9 mm wide, nearly sessile, smaller at base and apex of pinnular rachis, asymmetric about midvein, broadly linear, acuminate apically, rounded to truncate basally, sparsely puberulent along margins but otherwise glabrous, a few secondary veins visible. Capitula 9-24 mm in diameter at anthesis, in fascicles of 2-3 (-6) in leaf axils on actively growing shoots, the leaves developing with the capitula, the flowering shoot auxotelic with pods borne on older wood within crown (Fig. 10E), each capitulum with 55-170 flowers; peduncles (14-) 16-21 mm long, angled, pubescent with an involucre of bracts at the distal end. Flowers subtended by peltate bracts, 3-4 mm long, 0.7 mm in diameter; calyx 1.9-3.9 mm long, glabrous, finely ciliate along lobe margins, pale whitish green; petals 3-4.9 mm long, free, glabrous, pale whitish green; filaments 7.8-12.2 mm long, white; anthers hairy especially distally, white, apiculum absent; ovary 1.6-2.3 mm long, glabrous, white, with 13-20 ovules, style 4.2-10.5 mm long, white, with a terminal tubular stigma, exserted slightly beyond the anthers or included. Pods 1-2 (-4) per capitulum, 11-18.5 cm long, (7-) 10-19 mm wide, pendulous on sturdy 10-15 mm long stipes, linear-oblong or oblong, acuminate or sometimes obtuse apically, sometimes with a short beak, apparently readily broken off when dry, narrowly planocompressed, 9-20-seeded, valves mid-brown, glabrous, with reticulate venation most pronounced close to margins, membranous, the margins slightly thickened, dehiscent along both sutures. Seeds 6.5-8.8 mm long, 4-6.2 mm wide, compressed, circular to ovoid, deep chestnut-brown, glossy, aligned transversely in pods; pleurogram visible, deeply U-shaped, symmetrical. Chromosome number: 2n = 52 (Pan & Brewbaker 1988; Sorensson 1989). Fig. 43.
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