Trees, 8-9 m tall. Branchlets brown or reddish, cylindric, glabrous, with curved leaf scars. Leaf petiole 2-6 cm; petiolar gland circular, less than 0.5 mm high, 0.5-0.7 mm in diam., at upper portion of petiole and insertion of leaflets; rachis of pinnae 6-11 cm; pinnae 1 pair; petiolules ca. 4 mm; leaflets 3 pairs, opposite or subopposite, elliptic or lanceolate, 5-14(-20) × 3-5(-10) cm, both surfaces glabrous, lateral veins 3 or 4 pairs, conspicuous, base cuneate or acute, symmetric or not, apex acuminate. Heads 6-8-flowered, arranged in axillary panicles to 20 cm; peduncles 1-1.5 cm. Calyx urceolate or cup-shaped, 4.5-7 mm, glabrous; teeth inconspicuous. Corolla funnel-shaped or campanulate, (0.9-)1.2-1.5 cm; lobes narrowly ovate or elliptic, 4-5 mm, abaxially and apically sericeous. Staminal tube equaling corolla tube. Ovary glabrous; stipe 6-8 mm. Legume straight, cylindric, 10-20 × 3-3.5 cm; valves brown, leathery. Seeds to 7, ca. 2.5 × 2.5 cm, both ends turbinate; testa brown, crustaceous.