Large forest climber to at least 20 m. Tubers solitary 10–15 by 1–2.5 cm, cylindric to clavate, perennially replaced. Indumentum absent. Stems perennial, to 6.5 mm in diam. toward base, woody and densely spiny, usually unarmed distally, terete. Leaves simple, alternate to subopposite towards base, usually opposite or subopposite on distal stems; blade elliptic-oblong to ovate-elliptic, coriaceous, 3-veined, margins entire, base obtuse to rounded, apex acute to acuminate; petioles 1.3–4 cm long; cataphylls 3–7 by 5–6 mm. ovate, coriaceous; bulbils present in some races, 35–40 by 10–20 mm, cylindric to ovate or globose; lateral nodal organs absent. Inflorescences spicate, pendent, tepals free, inserted on a discoid torus, fleshy in texture; male inflorescences simple to compound, compound inflorescences 1(–2) per axil, simple/partial inflorescences 1–3 per axil, peduncles 3– 4.2 mm long, axes 1.5–5 cm long; female inflorescences simple or compound, compound inflorescences 1 per axil, simple/partial inflorescences 1(–2) per axil. Male flowers with outer tepals 1.8–2.1 by 1.4–1.8 mm, oblong to obovate-oblong, inner tepals 1.6–1.9 by 1.2–1.4 mm, obovate, thickened at base and along ventral midrib, stamens 6. Capsules 22–35 by 35–62 mm. Seeds 5–6 by 4–6 mm, orbicular- to ovoid-lenticular, wings 22–26 by 17–23 mm, extending all around seed margin.