Climber to 25 m. Tubers 1 to several, c. 10–50 by 5–30 cm, very variable in shape, in “wild” races usually cylindric to clavate, in cultivated races often globose to subglobose or clavate to digitate, known to be lobed or branched in parts of its range (Prain & Burkill 1938), with any underground part being able to give rise to a new plant. Indumentum absent. Stems 5–15 mm in diam. at base, woody and spiny, right-twining, usually quadrangular in cross section with a longitudinal wing on each angle (also petioles and often inflorescence axes). Leaves simple, opposite, blade ovate to broadly so on the lower stems, base often sagittate to auriculate, ovate with a cordate, rounded or truncate base on distal stems, chartaceous, (5–)7–9-veined, margins entire, apex acuminate; lateral nodal flanges present as a membranous semi-circular or auriculate wing at each node; cataphylls 6–10 by 2.5–4 mm, lanceolate to narrowly ovate; bulbils present in many cultivated races, 2–7 cm in diam., globose or subglobose to clavate, greybrown to dark brown with a smooth or finely warty epidermis. Inflorescences pendent, spicate; male simple ((1 –)2–6 (–10) per axil) or compound (1–2 per axil); partial/simple inflorescence axes flexuous; female inflorescences simple, 1(–2) per axil, elongating in fruit. Male flowers with outer tepals 1.3–1.6 by 1.0–1.3 mm, broadly obovate, inner tepals 0.9–1.1 by 0.8–0.9 mm, obovate to shortly spatulate; stamens 6, erect. Capsules 18–23 by 25.5–43.5 mm. Seeds 5–7.5 by 5–6.3 mm, wings 18–21.5 by 15– 21.5 mm, all around seed margin.