Twining shrubs; branchlets pubescent, glabrous later; axillary buds ovate, 2-3 mm. Petiole 7-15 mm; leaf blade oblong, broadly oblong, or oblong-elliptic, rarely orbicular, 6-12 × 4-7 cm, membranous during flowering period, papery or leathery during fruiting period, adaxial surface light brownish purple maculate, margin shallowly serrate, apex broadly cuneate or rounded. Inflorescences axillary and terminal, 3-9 cm, terminal inflorescences paniculate, with numerous flowers, axillary ones 3-5-or more flowered, tufted; pedicels 2-2.5 mm. Sepals obtuse-triangular, ca. 1.5 mm; petals oblong or rectangular-elliptic, 3-3.5 mm. Disk cupuliform, very shallowly lobed. Stamens ca. 2.5 mm; anther apically mucronulate; staminodes in female flowers ca. 1.5 mm. Pistils ca. 4 mm; pistillodes in male flowers ca. 1.5 mm. Capsule approximately globose, 6-7 mm wide. Seeds elliptic, sometimes slightly curved, ca. 4 mm. Fl. May-Jun, fr. Jul-Oct.