Lianas. Stem striate, pubescent at first, soon glabrescent. Leaves 3-foliolate; petiole 4-12 cm, pubescent at first, soon glabrescent; leaflets: petiolules 1-3 cm, yellowish villous; blade ovate or elliptic to oblong-elliptic, 8-12 × 4-8 cm, papery, lateral veins 4- or 5-paired, base cordate, asymmetric, apex shortly acuminate. Cymes axillary, compact, subcorymbose; rachis ca. 6 cm, generally shorter than petiole, yellowish villous; bracteoles oblong, ca. 3 mm. Flowers yellow. Outer tepals oblong, 5-6 × ca. 2 mm, abaxially glabrous, adaxially villous. Inner tepals similar to outer ones, subequal. Stamens 3-5 mm; filaments straight in bud, pubescent; appendages clavate, solid, small, ca. 1 mm. Ovary densely pubescent, ca. 2.5 mm; style 4-4.5 mm, hirsute. Interstaminal glands small, 3-lobed. Fruit 4-winged; wings: 2 large and 2 small, large ones 1.8-2.2 cm wide, thickly papery. Fl. May-Jun, fr. Aug-Sep.

The roots are used medicinally as a tonic for cattle.

● Dense forests, thickets on mountain slopes; (600-)1000-1900 m. Guangxi, Guizhou, Sichuan, Yunnan.