Tree, to 8 (23) m; calyx and axis of inflorescences puberulent, otherwise +/- glabrous. Leaves with (1) 2 or 3 pairs of leaflets; petioles terete to margined; rachis terete to narrowly winged; leaflets obovate to elliptic, retuse to obtuse or bluntly short-acuminate, acute and slightly inequilateral at base, the terminal pair 6-14 cm long, 3-6 cm wide. Spikes usually 1-5 in axils of terminal leaves; peduncles mostly 1-3 cm long; rachis mostly 4-9 cm long; bracts nearly obsolete, less than 1 mm long; flowers sessile; calyx tubular, 1-2 mm long, the teeth shallow, acute; corolla funnelform, 3-6 mm long, the lobes acute, ca 1 mm long, somewhat pubescent at apex; staminal tube included to long-exserted; stamens and style to ca 12 mm long. Legumes flat and ribbed to bulged in the middle with raised margins at maturity, mostly 7-15 cm long, 1.5-2.5 cm wide. Croat 5537, 6119. Mexico to Bolivia, Brazil, and Paraguay; Trinidad. In Panama, known from tropical moist forest in the Canal Zone, Veraguas, Herrera, Panama, and Darién, from tropical dry forest in Coclé (Penonomé), and from premontane wet forest in Panama (Cerro Azul).