Tall erect, or low bushy, spreading shrubs, 3-7 m high; branchlets angular, glabrous, or minutely pubescent when young; bark dark grey, roughened. <P>Phyllodes linear-lanceolate, oblong, narrowly elliptic, or obovate-oblong, 6-15 cm long, 8-35 mm broad, straight or almost so, 2-3 prominent, longitudinal parallel veins with many fine anastomosing veins between the main ones, apex acuminate or obtuse, usually mucronate; glands small but conspicuous on the upper margin near base. <P>Inflorescences simple, 1-2 per axil, sub-sessile; spikes rather dense or sometimes loose and interrupted, bright yellow, 2-4 cm long; receptacles glabrous; flowers 4-merous. <P>Legumes 5-10 cm long, 4-6 mm broad, cylindrical, straight or slightly curved, beaked, striate, brown, margins constricted between seeds. Seeds longitudinal in legume, obloid-elliptic; funicle short much folded, thickened into a large turbinate aril which is nearly as large as the seed.