Description from Flora of China
Baryxylum tonkinense Pierre, Fl. Forest. Cochinch. t. 391C. 1899; Peltophorum dasyrhachis (Miquel) Kurz ex Baker var. tonkinense (Pierre) K. Larsen & S. S. Larsen.
Trees, 12-20 m tall. Young parts and inflorescences densely ferruginous hairy, glabrescent; old branches with small ferruginous lenticels. Leaves 15-35 cm; rachis 8-25 cm; petiole robust, 3-15 cm; pinnae 6-13 pairs, opposite as leaflets; rachis 4-9 cm, sulcate, inflated at base; leaflets 5-14 pairs, abaxially pale green, adaxially deep green, oblong, 1.5-2 × 0.6-1 cm, adaxially smooth, ferruginous hairy on midvein at first, glabrescent, base attenuate, oblique, apex rounded, emarginate, or mucronate. Racemes subterminal, 8-10 cm. Flowers fragrant, yellowish, large. Pedicels 1-1.5 cm, ferruginous hairy. Receptacle discoid. Sepals subequal, oblong, 8-9 mm, lowest one narrower. Petals obovate-orbicular, ca. 1.5 cm, clawed, margin undulate, ferruginous villous on midvein on both surfaces. Filaments ca. 1 cm, inflated at base, densely ferruginous hairy; anthers oblong, ca. 3.5 mm. Ovary with short stalk, compressed, ferruginous hairy, 2- or 3-ovuled; style filiform, 2-3 × as long as ovary; stigma capitate. Legume reddish brown, fusiform, 8-13 cm, 2.5-3 cm at middle part, thinly leathery, asymmetric at both ends, acuminate, hairy at first, smooth and glabrous when old, winged on both sides; wings 5-7 mm wide. Seeds 3 or 4, yellowish when mature, compressed, obliquely obovoid, ca. 14 × 6 mm. Fl. Mar-Jul, fr. Apr-Oct.
Sparse forests, mountain slopes; 300-400 m. Fujian, Hainan [Cambodia, Laos, Vietnam].