Erect to almost spreading shrubs, with opposite leaves pubescent and usually glandular. Thyrsoid cymes terminal, sometimes short and axillary. Flowers small, usually purple, blue or white, shortly pedicelled to subsessile. Calyx campanulate, deeply 5-fid, somewhat enlarged and accrescent in fruit, persistent, lobes lanceolate to triangular. Corolla-tube short, cylindric; limb 2-lipped, subequally 5-lobed, with crisped or fimbriate slightly larger middle lobe of the lower lip, spreading. Stamens 4, didynamous, exserted; anther cells short, often divaricate below. Ovary imperfectly 4-locular, with 1 ovule in each locule; style filiform with shortly 2-fid stigma, often exceeding and curving above the anthers. Fruit a capsule, small, globose, with 4 incurved valves; seeds small, oblong, erect.
About 10 species, mostly Asian (Himalayas to Japan); represented here by 2 species.