Vines perennial, herbaceous, turning black on drying. Branches shallowly grooved, puberulous. Leaves 2-pinnate, 15-foliolate; petiole 4.4--5.8 cm; leaflet blades lanceolate to narrowly ovate, (3.7--)4.6--5.9(--6.2) × (0.8--)1.2--1.8 cm, papery, undivided or rarely 2-or 3-lobed, both surfaces sparsely puberulous to sometimes adaxially subglabrous, base broadly cuneate to cuneate, margin entire, apex attenuate to acuminate; basal veins abaxially ± prominent. Cymes axillary or terminal, few flowered; peduncle 2.5--5 cm; bracts ternate or simple, narrowly ovate, 3-parted. Flowers 1.3--2.5 cm in diam. Pedicel 0.7--1.3 cm, puberulous. Sepals 4, white, spreading, oblong, 10--15 × 4--6 mm, abaxially densely puberulous, adaxially puberulous, apex acute to obtuse. Stamens 4--8 mm, glabrous; anthers oblong, ca. 2.4 mm, apex obtuse. Ovaries pubescent. Style ca. 7 mm, densely villous. Achenes elliptic to ovate, 2.8--4.2 × ca. 2 mm, pubescent; persistent style 2.5--4 cm, brown to yellowish brown plumose. Fl. Aug--Oct, fr. Aug--Oct.