Glabrate or hairy, unarmed perennial herb with rhizomes bearing large terminal tubers; stems to c. 1 m tall, ± winged, much-branched. Petiole to 10 cm long. Lvs to c. 40 cm long, imparipinnate; false stipules at base to c. 2 cm long, oblique or semi-lunate; main leaflets 5-9, variable, mainly stalked, glabrate or hairy, entire, with small, very unequal, broad leaflets between. Lamina of main leaflets usually to 12-(15) × 7-(8) cm, broad-ovate, elliptic-ovate or oblong-ovate; base ± cordate, often obliquely so; apex usually obtuse or acuminate with a blunt apex, sometimes acute. Cymes loose, with few-15 fls; peduncles long and slender, often > 12 cm long; pedicels deflexed at fruiting. Calyx 6-10 mm long, hairy; lobes lanceolate or linear-lanceolate, > tube, somewhat accrescent. Corolla 2-4 cm diam., white to mauve or purple; lobes triangular and undulate, reflexing, somewhat hairy outside, especially on margins. Anthers 6-9 mm long. Berry 1-3 cm diam., globose or subglobose, green; stone cells 0. Seeds c. 2 mm long, obovoid to ± ellipsoid.