Description from Flora of China
Inga pterocarpa Candolle, Prodr. 2: 441. 1825; Caesalpinia ferruginea Decaisne; C. inermis Roxburgh; Peltophorum ferrugineum (Decaisne) Bentham; P. inerme (Roxburgh) Naves ex Fernández-Villar; P. roxburghii (G. Don) O. Degener; Poinciana roxburghii G. Don.
Trees, 4-15 m tall. Young shoots, petioles, and inflorescences ferruginous hairy; old branches with yellowish, small lenticels. Leaves 30-42 cm; petiole robust; rachis 25-35 cm; pinnae 7-15 pairs, opposite, 8-12 cm; leaflets (7-)10-21 pairs, crowded together, oblong-obovate, 1.2-1.7 cm × 5-7 mm, leathery, abaxially pale green, adaxially deep green, base oblique, margin entire, apex rounded, mucronate. Panicles terminal or axillary, densely ferruginous puberulent; bracts caducous, 5-8 mm. Pedicels ca. 5 mm, ca. as long as flower buds, 5-7 mm from one another. Flower buds globose, 5-8 mm in diam. Sepals ovate, 5-8 × 4-7 mm, outside ferruginous tomentose. Petals obovate, 1.5-1.7 cm × 8-10 mm, densely ferruginous pubescent at middle of both surfaces, long clawed. Filaments ca. 1.2 cm, hirsute at base; anthers ca. 3 mm, sagittate at base. Ovary stalked, hairy, 3- or 4-ovuled; style filiform, much longer than ovary, smooth; stigma discoid, 3-lobed. Legume winged, compressed, fusiform, narrowed to both ends, longitudinally veined at middle part; wings 4-5 mm wide. Seeds 2-4. 2n = 26.
Cultivated in Guangdong (Guangzhou), Guangxi, Yunnan [Bhutan (cultivated), India, Indonesia, Malaysia, Sri Lanka, Thailand, Vietnam; Australia, N Oceania; introduced in E Africa and many other tropical countries].