Climbing shrub up to 12 m high; stems quadangular, grooved, scabrid with minute reflexed prickles. Leaves opposite, ovate to narrowly or broadly triangular, 4–9 cm long, 2.5–6 cm broad, base truncate to cordate, apex acuminate, margins usually coarsely toothed near the base, glabrous above, aculeate on veins beneath; petioles 1–3 cm long, aculeate. Flowers 1–2 in each distal axil forming a pendent inflorescence; pedicels 3–5 cm long; bracteoles 2, linear, 2–4 cm long. Calyx tube 8 mm long; lobes broadly deltoid, 8 mm long, acute, sparsely aculeate. Corolla pink to mauve, tube ± 3.5 cm long, cylindrical, basal part 5 mm in diameter, widening to throat to about 2.5 cm in diameter; lobes 1.5–2.5 cm long and broad. Stamens 2 + 2; anthers 8 mm long. Ovary glabrous; style up to 6 cm long; stigma globose, 4–5 mm in diameter. Capsule ovoid, ± 1 cm in diameter, dehiscing loculicidally with 4 valves. Fig. 31, p. 107.
