Annual or perennial non-aromatic herbs, glabrous to scabrid or villous with eglandular hairs. Leaves opposite or in whorls. Inflorescence of many-flowered ± distant verticillasters, not borne in leaf axils, forming loose or condensed spikes. Uppermost leaves transitional to bracts, sometimes coloured. Calyx ovoid-campanulate in fruit, tubular and often transversely ribbed in fruit, slightly bilabiate; uppermost lobe broader than 4 lower lobes, not decurrent on tube; tube glabrous or pubescent within. Corolla small, slightly bilabiate; tube short; upper lip 4-lobed, lower lip entire. Stamens 4, inconspicuously declinate; filaments not appendiculate; thecae becoming unilocular. Nutlets ellipsoid or ovoid, smooth or punctulate.