Description from Flora of China
Trees, 4-10 m tall. Leaves 10-20 cm; rachis and petioles densely rusty tomentose; stipules very caducous, ovate-lanceolate; leaflets (7 or)9(or 11-13); petiolules ca. 3 mm, densely rusty tomentose; blades ovate to ovate-lanceolate, 1.5-4(-7) × 0.8-1.6(-2.8) cm, firmly papery, abaxially glabrescent or sparsely appressed puberulent, adaxially glabrous except for puberulent midvein, base cuneate or rounded, apex acuminate or obtuse, sometimes mucronate. Panicles axillary or infra-axillary, rather compact, ca. 6 × 5.5 cm; peduncles slightly stout, glabrous. Pedicel ca. 5 mm; bracts ovate; bracteoles deciduous, lanceolate, sparsely pubescent. Calyx campanulate, ca. 5 mm; tube outside glabrous below, sparsely puberulent above, 5-toothed; teeth ciliate, unequal, lowest lanceolate, ca. as long as tube and longer than others, lateral 2 triangular; upper pair ovate, subconnate. Corolla white; petals distinctly striate; standard broadly ovate, base attenuate to short, broad claw; oblong wings and half-moon-shaped keel with downward broad auricles on upper side below. Stamens 10; filaments connate at base, irregularly separated to incompletely 3-5-adelphous on upper part. Ovary glabrous except for pubescent long stipe, 3- or 4-ovuled; style subulate-conical; stigma minute. Legume oblong to strap-shaped, (4-)7-9.5 × 1.5-2.8 cm, leathery, glabrous except for short stipe, distinctly reticulate opposite 1 or 2 seeds. Seeds reniform to subreniform-oblong, compressed, ca. 9 × 4 mm; testa black, shiny. Fl. Mar, fr. Apr-May.
Mountain slopes, thickets, bushes; 1000-2000 m. Guangxi, Guizhou, Yunnan [N Vietnam].