Annual or perennial herbs with a pilose to villous eglandular indumentum of simple hairs. Leaves undivided, entire to crenate-serrate, petiolate at least on lower leaves, usually gland-dotted. Verticillasters many-flowered, distant from each other, borne in axils of upper leaves. Bracts numerous, subulate to ovate-lanceolate, shorter than to as long as calyces. Flowers white, sometimes with cream, rose or green markings. Calyx with 10 often ribbed veins, tubular, straight or curved; mouth truncate to prominently oblique, pilose to vinous at throat; teeth 8-10, equal or unequal. Corolla rather small, bilabiate; tube included in calyx, internally oblique-annulate or not; upper lip hooded or ± straight, densely white-bearded; lower lip with a median lobe clearly larger than laterals, usually much longer than upper lip. Stamens 4, didynamous, included within corolla upper lip; thecae 2-locular, eventually confluent. Style shortly 2-lobed. Nutlets 4, oblong, trigonous, obtuse to truncate-rounded at apex.