Climber to 3 m. Tubers 4–10, subtended by a woody crown, cylindric, to 20 cm long, c. 5 mm in diam., spreading to vertically oriented, annually replaced, apices 2–6.5 by 1–3.1 cm, clavate to globose. Indumentum absent. Stems 1.5–2.5 mm in diam., twining to the right, annual, towards base firm and spiny, unarmed on upper stem, occasionally branching when creeping on substrate, slender, terete. Leaves simple, opposite, blades ovate to broadly ovate, 5–7-veined, chartaceous, margins entire, base obtuse to cordate, apex acuminate; petioles 1.4–5.3 cm long; lateral nodal organs present especially towards stem base as a swollen petiole base, forming a sheath around the axillary branch where present, usually bearing pungent, straight to curved, straw-yellow spines; cataphylls 3–4.2 by 2–3.5 mm, ovate; bulbils occasionally present in leaf axils when stems covered by or touching the soil, 17–27.5 by 2–10 mm, usually ovoid to globose, sometimes irregularly digitate, smooth to tuberculate. Inflorescences spicate, pendent, simple, tepals inserted on a small discoid torus, free, fleshy in texture with inner whorl tepals thicker than outer; male inflorescences 1–3(–4) per axil, peduncles 2–5 mm long, axes 0.7–4 cm long; female inflorescences 1 per axil, 3–5 cm long including peduncle, 1–3(–4) capsules developing. Male flowers with outer tepals 1.2–1.6 by 0.9–1.3 mm, oblong, inner tepals 1.1–1.5 by 0.7–1 mm, obovate, stamens 6. Capsules 12–15.5 by 18–32 mm. Seeds 5.1–8 by 4.5–7 mm, lenticular-ovoid, wings 14–17 by 13–17 mm, extending all around seed margin.