Glabrous or hairy, unarmed shrubs or herbs with opposite or whorled, entire or ± crenate leaves. Flowers showy, yellow or red, mostly long peduncled, in subterminal spikes; bracts 4-ranked, large, ovate-lanceolate, imbricate; bracteoles linear-lanceolate, shorter than calyx, hairy. Calyx deeply 5-lobed, lobes unequal. Corolla tube narrow, longer than limb, incurved, limb deeply divided to throat forming a 5-lobed lip, lobes unequal, imbricate. Stamens 4, all fertile, included, anthers longer than filaments, monothecous, sterile theca bearded throughout, muticous, connective mucronate. Ovary bilocular, locules 2-ovuled; style thickened upwards, stigma minutely 2-fid. Capsule oblong, flattened, ± quadrangular, 4-seeded. Seeds ellipsoid-ovate, beset with fringed scales or hairs.