Benth. in Hook., London J. Bot. 4:587. 1845
Tree, to 27 m tall and 40 cm dbh, glabrous to puberulent throughout; trunk ± involuted with many prominent horizontal wrinkles; outer bark thin; inner bark reddish; young stems very prominently lenticellate. Petioles margined; rachis margined to narrowly winged; leaflets in 2-5 (usually 4) pairs, narrowly ovate to lanceolate-elliptic or oblanceolate, acuminate, rounded to acute at base, slightly asymmetrical, the terminal pair 8-22 cm long, 2.5-8 cm wide. Spikes axillary in groups of 1-6; peduncles 1.5-3.5 cm long; rachis shorter than peduncle, very densely flowered, 0.5-3 cm long; bracts ca 5 mm long; flowers sessile; calyx 1-2 (3) mm long, the lobes ca 0.5 mm long, blunt; corolla 4-8 mm long, the lobes blunt to acute, ca 1 mm long; stamens and style ca 1 cm long. Legumes flat, 10-22 cm long, (2) 2.5-3 cm wide, ± glabrous, ± straight, the marginal ribs prominent, the seminiferous areas individually raised, the axes of the inflorescences persisting with warty bases of fallen fruits. Croat 14881.
Common in the forest, especially the young forest. Flowers most commonly in May and June, beginning as early as December. The fruits mature in the rainy season.
Separated from I. ruiziana by the lanceolate-elliptic leaflets, which are always in less than six pairs, and by the shorter calyx, usually less than 2 mm long.
Panama to Brazil. In Panama, known from tropical moist forest in the Canal Zone and from premontane wet forest in Panama (Cerro Jefe).