Large forest climber to at least 30 m. Tuber to 40 cm in diam. and at least 5 kg in mass, shape variable, usually globose to subglobose with several shallow lobes, perennial. Indumentum present on all parts but plants glabrescent, hairs simple, 0.2–0.6 mm long. Stems 7–15 mm in diam. towards base, perennial, twining to the left, towards base stems woody and very spiny, with 6–8 hard, vertically orientated flanges at each swollen stem node, upper stems with few spines or unarmed except paired lateral nodal spines, terete. Leaves simple, alternate, blade broadly sagittate-ovate to broadly ovate towards stem base, subdeltoid to ovate on the upper stems, 5–7-veined, coriaceous, margins entire, base cordate to sagittate, truncate or rounded, apex acuminate; petioles 2.5–10.5 cm long; lateral nodal spines 1.8–7 mm long, straight to recurved, on either side of each node; bulbils and cataphylls absent. Inflorescences pendent, tepals inserted on cup-shaped torus, fused at base, ascending to reflexed; male inflorescences simple or compound, compound inflorescences 1 per axil, simple/partial inflorescences racemose, 1–2(–3) per axil, with cymules of 1–3 flowers at each node, peduncles 1.2–5.3 cm long, axes 2.3–16(–25) cm long; female inflorescences spicate, simple, 1 per axil. Male flowers 3.5–4.2 mm in diam. at anthesis, pedicels 1.1–2.5 mm long; outer tepals 1.2–2.6 by 0.7–1.4 mm, ovate-oblong, inner tepals 1.8–2.5 by 1.1– 1.5 mm, ovate to ovate-oblong; stamens 6. Capsules 33–58 by (13–)16–23 mm. Seeds 10–13.5 by 5–7.5 mm, lenticular-ovoid; wing (11–)15–25 by 6.5–11.5 mm oblong, extending from seed apex, outer margin often lobed.