Tubers vertical, cylindric. Stem twining to left, glabrous. Leaves alternate, simple; petiole 3--6 cm; leaf blade ovate-cordate, 6.5--10 × 5--9 cm, glabrous, smooth, veins sparsely and minutely puberulent abaxially, base cordate with rounded sinus, apex acute or acuminate, shortly pointed at tip. Male thyrse to 25 cm, densely and minutely hairy. Male flowers: in sessile, dense cymules of 3--6, sessile; bracts ovate, ca. 0.5 mm, apex acute; perianth saucer-shaped, ca. 0.35 mm, tube short, lobes incurved, broadly ovate, ca. 0.75 mm; stamens 6, inserted in perianth tube, filaments equaling perianth tube, anthers small, introrse. Infructescence ca. 9 cm. Capsule reflexed, light brown, ellipsoid, to 1.6 cm, base rounded, apex slightly emarginate; wings to 0.6 cm wide. Seeds inserted near middle of capsule, winged all round. Fl. Jul--Sep.

Forests in mountain ravines; 1300--1500 m. SW Yunnan [Myanmar, N Thailand].