Description from Flora of China
Twiners woody or herbaceous. Leaves petiolate, ovate to circular, abaxially spotted with minute glands, as black dots in dried specimens, base usually cordate, margin entire. Cymes axillary, 1- to many flowered, peduncled; bracts early deciduous, small. Sepals ovate to elliptic or circular, equal or slightly unequal, much enlarged in fruit, ± leathery, abaxially glandular punctate, margin membranous, apex obtuse to emarginate. Corolla funnelform, midpetaline bands ± pilose and with minute glands. Stamens and pistil included; filaments filiform, inserted near corolla base; pollen globular, pantoporate, finely spiny. Disc ring-like. Ovary glabrous, 4-loculed; ovules 1 per locule. Style 1; stigma 2-globular. Fruit enclosed by enlarged calyx, globose; pericarp thin, eroding irregularly between septa to produce a lanternlike effect. Seeds 4 or fewer, pubescent.
Approximately 12 species: Africa, Asia; one species in China.