Rootstock unknown. Stem twining to left, ca. 2 mm thick at anthesis, glabrous. Leaves alternate, simple; petiole to 4 cm; leaf blade drying green adaxially, grayish abaxially, narrowly ovate to oblong-lanceolate, to 12 × 6 cm, membranous, glabrous, basal veins (5 or)7, outermost ones poorly developed, base cordate with broadly rounded sinus, apex acuminate. Male spike solitary, to 20 cm, slender. Male flowers: solitary, subsessile; pedicel to 0.5 mm; bract ± lanceolate, ca. 1 mm; bracteole borne on pedicel, ovate, 0.5--0.75 mm; perianth saucer-shaped, outer lobes ovate, ca. 1.5 mm, apex recurved, subacute, inner ones more rounded at apex than outer; stamens 6, inserted at margin of receptacle, filaments mostly erect, sharply incurved at apex, anthers nearly as wide as long. Female spike solitary, pendent, to 7 cm. Capsules 3 or 4, not reflexed, light brown, ca. 3 cm, glabrous, base truncate to broadly cuneate, attenuate into pedicel, apex shallowly emarginate; wings to 2.6 cm wide. Seeds inserted near middle of capsule, winged all round. Fl. Aug, fr. (immature) Oct.