Herbs or subshrubs, with rhizomes or stolons. Stems erect or ascending, simple or branched from base. Leaves simple, petiolate or subsessile, cordate to lanceolate, penniveined. Verticillasters 2-6-flowered, in false spikes, terminal racemes, or panicles of racemes; bracts rhombic-ovate to linear-lanceolate, margin entire or dentate. Calyx 10-veined, throat glabrous to pilose annulate; tube tubular to campanulate, swollen in front at base; limb equally 5-toothed to 2-lipped, upper lip 3-toothed, lower lip 2-toothed. Corolla 1-lipped; tube included or exserted, not hairy annulate inside; limb 5-lobed, with middle lobe circular or spatulate, occasionally 2-lobulate; lateral lobes 4, small. Stamens 4, anterior 2 slightly longer, all exserted from posterior sinus of corolla; anther cells divaricate. Ovary globose. Style equal to or slightly longer than stamens, equally or subequally 2-cleft at apex. Nutlets obovoid, glabrous, smooth to netted, areole ca. 1/2 as long as nutlet.

Approximately 260 species: worldwide, but abundant in the Mediterranean region; 18 species in China.