Description from Flora of China
Herbs, perennial, 30-60(-150) cm tall, many branched, puberulent, densely spreading villous, or glabrescent. Stems nearly erect to spreading, with a woody base, ridged. Leaves 9-17(-21)-foliolate; rachis 7-15 cm, including petiole ca. 1 cm; leaflet blades oblong-elliptic, oblanceolate-elliptic, or obovate-elliptic, 1.5-3.5(-4.5) × 0.4-1.5 cm, secondary veins 7-12 on each side of midvein, base narrowly rounded, apex obtuse, truncate, or retuse and cuspidate. Pseudoracemes terminal, opposite to a leaf or axillary near apex of branchlets, ca. 2 or 10-15 cm. Pedicel 2-4 mm, slender, slightly elongate in fruit. Flowers ca. 8 mm. Calyx 2-4 × ca. 3 mm; teeth equal. Corolla mauve; standard orbicular, white puberulent. Ovary with trichomes, with 5-8 ovules. Legume linear, 3-5 cm × 3.5-4(-6) mm, with sparse appressed trichomes, apically slightly curved. Seeds ca. 6 per legume, grayish brown, ellipsoid, ca. 3 × 1.5 mm, with or without spots, smooth or rough. Fl. Mar-Oct, fr. Sep-Dec.
Open places, slopes, sandy grasslands by oceans, grasslands by river margins; near sea level to 700 m. Fujian, Guangdong, Guangxi, Hainan, Sichuan, Taiwan, Yunnan [Cambodia, India, Indonesia, Laos, Malaysia, Nepal, Sri Lanka, Thailand, Vietnam].