Rhizome horizontal, irregularly branched, cylindric, to 1.5 cm thick, hard. Stem twining to left, glabrous, smooth except inconspicuously shortly prickly near nodes. Leaves alternate, simple; petiole 6--8 cm; leaf blade drying grayish brown, triangular-ovate or nearly triangular-sagittate, 10--12 × 6--10 cm, thinly leathery, glabrous, basal veins 3--7, outermost ones much shorter, reticulate veins prominent, base auriculate, apex acuminate. Male spikes solitary or 2--4 together, to 20 cm. Male flowers: solitary or paired; pedicel ca. 2.5 mm; perianth lobes ± reflexed, oblong or oblong-ovate, outer ones ca. 1 mm, wider than inner ones; stamens 6, inserted at margin of perianth tube, less than 0.8 mm. Female spikes similar to male ones. Capsule bronze, shiny, ovoid-globose, 2.8--3.2 cm, apex truncate; wings ca. 1.5 cm wide. Seeds inserted near middle of capsule, winged all round. Fl. Jun--Aug, fr. Aug--Oct.

Forests, scrub; near sea level to 200 m. Hainan [Cambodia, Laos, Malaysia, Thailand, Vietnam].