Variable climber to 25 m. Tubers 3–5(–10), to 50 cm long and 3–5 cm in diam. (towards apex), annually replaced, narrowly cylindric with a globose to clavate apex, subtended by a woody crown, parenchyma largely fibrous. Indumentum absent except for the pubescent axillary buds, and the pale green to white waxy coating on the leaf lower surface and immature capsule (most visible in living material). Stems 2–5 mm in diam., twining to the right, annual, towards base usually woody and spiny, unarmed on upper stem, smooth and terete. Leaves simple, opposite, sometimes alternate to subopposite toward base, blade shape variable, but usually ovate, elliptic, or elliptic-oblong, sometimes ovate-sagittate, chartaceous to subcoriaceous, (3–)5–7-veined, margins entire, base rounded or truncate to cordate or auriculate, rarely cuneate, apex acute; petioles (1–)2.5–6.5 cm long; cataphylls not seen; bulbils and lateral nodal organs absent. Inflorescences spicate, pendent, tepals inserted on a discoid torus, free, fleshy in texture with inner whorl tepals usually thicker than outer; male inflorescences simple or compound, compound inflorescences 1–2 per axil, simple/partial inflorescences 1–6 per axil, peduncles 0.3–2.5 mm long, axes 0.8–3.5 cm long; female inflorescences simple, 1–2 per axil. Male flowers with outer tepals 1.5–1.8 by 1.1–1.3 mm, ovate-oblong; inner tepals 1.2–1.5 by 0.9–1.1 mm, obovate, stamens 6. Capsules 13–19 by 25–36 mm, opercular strip not possessing a membranous margin. Seeds 4.9–6 by 4.5–5.2 mm, ovoidlenticular, wings 14.5–18.5 by 12.5–16.6 mm, extending all around seed margin.