Leaves paired, small, shortly petiolate; stipules in lower part of stem with sheath produced into an undivided triangular lobe, in the upper part deeply bifid into narrowly triangular fimbriae or less often with 3 fimbriae.
Ovary 2-locular, with peltate placentas and 8 to fairly numerous ovules; style stoutly filiform, minutely bifid at apex, the stigma lobes short, subglobose or ellipsoid.
Fruit capsular with bony walls, ellipsoid, produced into a solid beak; at length apically loculicidally dehiscent Seeds few per locule, blackish, angular, pitted.
Calyx tube ovoid or ellipsoid; lobes 4, equal, oblong-elliptic or oblong-spathulate, rather thick, exceeding the tube, joined at the base to form a free tube.
Corolla tube shortly cylindrical or narrowly funnel-shaped, sparsely pilose inside; lobes 4, elliptic-oblong to oblong-lanceolate.
Flowers small, hermaphrodite, dimorphic, in terminal triads or sometimes solitary.
Stamens completely exserted in short-styled forms.
Prostrate perennial herb.