Perennial herbs with quadrangular stem. Leaves simple, opposite, petiolate, exstipulate. Inflorescence spicate and flowers becoming strongly reflexed after fruiting. Bracts and bracteoles linear and small. Flowers herma¬phrodite, zygomorphic, pink or pale purple. Calyx bilabiate, tubular, persistent, lobes 5, unequal. Corolla tubular, 5 lobed, bilabiate, lower lip larger than the upper. Stamens 4, didynamous, included or slightly exserted, anthers bithecous, subreni¬form, dehiscing longitudinally, pollen grains tricolpate, subprolate. Carpels 2, syncarpous; ovary superior, oblong, unilocular, ovule solitary, nearly erect from the base, orthotropous; style terminal; stigma simple, very shortly bifid. Fruit caryopsis with membranous pericarp, enclosed by the persistent, ribbed, reflexed, 3 hooked calyx. Seeds exalbuminous; embryo oblong, cotyledons oval and folded.