Woody shrub or small tree with massive, irregular, light green, fleshy or hard bole up to 0·50 × 2·5 m., producing slender, greyish-green, very thorny unbranched fertile stems c. 1 m. long, sometimes climbing by means of the thorns, with internodes 0·5–4 cm. long. Leaf-lamina 1–3·5 × 0·7–3 cm., ovate to elliptic, obtuse or sometimes retuse at the apex, margin entire or somewhat remotely shallowly lobulate and undulate, rounded or cordate at the base, ± coriaceous, greyish-glaucous green, with the midrib, lateral nerves and vein reticulation distinct on both surfaces but more so below; petiole 0·2–0·7 cm. long. Glands of the lamina-base 1 or 2, 1–2·5 mm. in diameter, subreniform to orbicular, sessile at the apex of the petiole; lamina-gland 1, apical or subapical, c. 0·25 mm. in diameter, at the end of the midrib. Stipules c. 0·5 mm. long, triangular, acute. Sterile tendrils 3·5–6 cm. long, axillary, soon becoming sharp patent thorns up to 4 cm. long. Cymes axillary, 2–6-flowered in male, 1–3-flowered in female; peduncle c. 0·5 cm. long; pedicels 0–2 mm. long in male. 0–1 mm. long in female. male flower: (10)12–24 × 2·5–4 mm. (incl. the 1·5–3 mm. long stipe), tubular-campanulate; hypanthium 1–3 mm. long, cup-shaped; sepals (8)9–18 mm. long, free, lanceolate, obtuse, entire; petals (6)8–10 × 1–2 mm., lanceolate, acute, serrulate, 1–3-nerved; corona consisting of a few stiff hairs near the insertion of the petals; stamens with the filaments 2·5–5·5 mm. long, connate at the base, inserted at or up to 1·5 mm. above the base of the hypanthium; anthers 4–5 × 0·75–1 mm., obtuse, with apiculum up to 0–2 mm. long; disk-glands 0 or reduced to callose pads up to 0·25 mm. in diameter; vestigial ovary 0·5–1 mm. long on a gynophore 0·5–1 mm. long. female flower: smaller than the male; hypanthium 1–1·5 mm. long; sepals 5–8 mm. long, lanceolate, obtuse; petals 2·5–3·5 × 0·5–0·75 mm., lanceolate, 1-nerved; corona 0 or consisting of a few stiff hairs; staminodes c. 1·5 mm. long, connate at the base, inserted at the base of the hypanthium; disk-glands 0; pistil 4–6(8) mm. long; gynophore 1–2 mm. long; ovary 2–4(5) × 2–3·5 mm., subglobular; styles connate for c. 1 mm. at the base, with the free arms c. 0·5 mm. long; stigmas c. 1 mm. in diameter, papillate. Capsule 1·4–2·2 × 1·2–1middot;8 cm., subglobular, with thinly coriaceous pericarp, 3–6-seeded. Seeds c. 6·5 × 7 × 2–2times;5 mm., suborbicular, pitted.