Description from Flora of China
Herbs annual or perennial. Leaves petiolate, dentate. Cymes axillary, 2-12-flowered, short pedunculate; bracts lanceolate-subulate. Calyx tubular to tubular-campanulate, 13-veined, throat not constricted, sparsely hirsute inside, base not or only slightly saccate in fruit, limb 2-lipped; teeth of upper lip 3, reflexed; teeth of lower lip 2, longer than upper teeth, lanceolate. Corolla almost as long as calyx to much exserted, 2-lipped, tube gradually dilated; upper lip emarginate, straight; lower lip reflexed, 3-lobed, middle lobe longer than lateral lobes. Stamens 4, didynamous, all included or anterior 2 exserted; anther cells 2, ± parallel or divergent. Ovary glabrous. Style shorter than corolla, complanate or 2-cleft at apex. Nutlets ovoid, rounded.
About six or seven species: Africa, Asia, Europe; one species in China.