Trees 2–15 m tall. Leaves slightly congested at the branch tips, imparipinnate with (1–)2–3(–4) pairs of lateral leaflets, obtrullate in outline, (1.3–)2.6–4.2(–7.0) × (1.5–)2.2–3.6 cm; rachises densely tomentose, points of leaflet attachment with a tuft of long, lanate hairs; stipular sheaths apically acute with spurs, densely lanate on the outer surfaces; leaflets elliptic to obovate in outline, second pair from the terminal leaflet the largest, one of this pair (0.9–)1.2–2.2 × 0.4–1.1 cm; margin entire or slightly crenate at the apex with 3–5 teeth, apically deeply emarginate, basally unequally cordate; upper leaflet surfaces glabrous; lower leaflet surfaces densely tomentose with whitish hairs 0.6–1.5 mm long. Inflorescences pendant, (2.3–)4.3–13.8) cm long, bearing 5–9 flowers; floral bracts 3.1–8.0 mm long, narrowly triangular, densely lanate on the outer surface; rachises tomentose. Flowers 6.2–12.2 mm diam.; sepals 4, ovate, green, densely tomentose outside; stamens 7–9, anthers orbicular, with a dense tuft of straight white hairs on the upper half; styles fimbriate, 2.6–3.9 mm long. Fruits turbinate, with variable numbers and placement of flattened spines, densely villous; 3.4–6.0 × 2.9–8.3 mm including spines. Diploid and hexaploid.