Shrubs, climbing. Branchlets subterete, tomentose with stellate and/or simple hairs. Leaves opposite. Cymes capitate, 3-9-flowered, arranged in panicles, pedunculate; involucral bracts 4 or by fusion reduced to 3 with third bract deeply emarginate. Calyx funnelform or campanulate, 5-dentate, slightly enlarged in fruit. Corolla with a slender tube, outside glabrous, pubescent in throat, 2-lipped, lower lip 3-cleft, upper lip 2-cleft. Stamens 4, didynamous, inserted at corolla throat; anthers subglobose. Ovary obovate, apex glandular, imperfectly 2-locular; ovules 2 per locule. Stigma capitate or shortly 2-cleft. Fruit obovate, indehiscent.

About ten species: mainly in SE Asia, two species in China.