Tree, to 15 m tall; branchlets sparsely strigose when young, glabrate in age, minutely lenticellate, minutely ribbed below petioles (at least when dried). Leaves strigose throughout, especially on axis and midrib of leaflets; petiole and rachis terete to narrowly margined; leaflets in 2 or 3 pairs, lanceolate to elliptic, long-acuminate, acute to rounded at base, the terminal pair 9-18 cm long, 3.5-7.5 cm wide. Spikes axillary, in groups of 1-7; peduncle and rachis strigose; peduncles 2-4 cm long; rachis much shorter, 1-2.5 cm long; bracts subulate, to +/- 2 mm long; calyx puberulent, 3-5 mm long, the lobes +/- 1 mm long; corolla moderately sericeous, 5-9 mm long, the lobes to 2 mm long; stamens and style to ca 2 cm long. Legumes flat, to 16 cm long and 2 cm wide, minutely puberulent, the margins raised. Croat 7418. Common in the forest. Flowers throughout the rainy season (May to December, rarely to January). One individual on BCI flowered for a week in early June in two consecutive years. Mature fruits seen in late dry season. Fruits are similar to those of I. pezizifera, but that species lacks persistent warty fruit bases. Mexico to Peru; West Indies. In Panama, known from tropical moist forest in the Canal Zone, Bocas del Toro, San Blas, Veraguas, Panama, and Darien, from premontane wet forest in Colon, Chiriqui, Coclé, and Panama, from tropical wet forest in Panama and Darien and from lower montane wet forest in Chiriqui. Reported from premontane rain forest in Costa Rica (Holdridge et al., 1971).