Dioecious, erect shrub up to 90 cm tall with (1–)2 spines 0.5–5 cm long in each leaf axil, sometimes scandent with stems up to 8 m long; branchlets terete or quadrangular, glabrous to densely hairy. Leaves decussately opposite, simple and entire; stipules absent or rudimentary; petiole short; blade elliptical-oblong to ovate-oblong or orbicular, 1.5–5.5 cm × 0.5–4.5 cm, base rounded or somewhat narrowed, apex mucronate, pinnately veined with one pair of lateral veins from near the base. Inflorescence an axillary, sometimes terminal spike or cyme up to 3 cm long or flowers solitary; bracts ovate, often with long and spinous mucro. Flowers unisexual, regular, 4-merous, usually sessile; calyx campanulate, 2–4 mm long, with triangular lobes; petals linear-oblong to oblong, greenish to yellowish, the upper part reflexed over the calyx, 2–5 mm long; male flowers with stamens inserted at the base of the rudimentary ovary, exserted; female flowers with staminodes and superior ovary, up to 4.5 mm long with a broad sessile stigma. Fruit a globose berry, 0.5–1 cm in diameter, 1–2-seeded, green turning white, with persistent stigma. Seeds disk-like, brown to black. |