Walp. & Duch., Linnaea 23:746.1850
Tree, to 10 m tall; branchlets densely ferruginous-tomentose when young, glabrate in age. Leaves velutinous especially on axes and veins, sparsely so on upper surface; petioles very short, terete; rachis cuneate-winged; leaflets in 3 or 4 pairs, ovate to elliptic, acute to short-acuminate, obtuse to rounded at base, asymmetrical, the terminal pair 7-16 cm long, 3-7 cm wide, the basal pair often much reduced. Spikes axillary or terminal, solitary or in pairs; peduncle, rachis, and calyx densely ferruginous-tomentose; peduncles 1.5-2.5 cm long; rachis 1.5-3.5 cm long; bracts to 3 mm long; flowers sessile; calyx 8-15 mm long, the lobes to ca 3 mm long; corolla 13-18 mm long, sericeous, the lobes ca 3 mm long; stamens and style to ca 50 mm long. Legumes subterete, with broad ribs, densely ferruginous-pubescent, mostly 4-20 cm long, 1-2 cm diam, often curled, yellowish-brown at maturity. Croat 6105, 13967.
Common along the shore. Flowers from March to July. The fruits probably mature from July to October. Easily confused with I. hayesii and I. vera. It may be distinguished from I. hayesii by its more or less terete fruit and more densely pubescent calyx, and from I. vera by having fewer than five pairs of leaflets.
Known only from Panama, from tropical moist forest in the Canal Zone, Veraguas, Panamd, and Darien and from premontane wet forest in Panama. (Cerro Campana).
See Fig. 264.