Calyx 18–24(27) mm. long, somewhat inflated, more or less densely glandular-pilose; lobes 4–8(14) mm. long, unequal, lanceolate-triangular, acute or obtuse.
Leaves opposite, 6–20 x 1.5–7 mm., oblong-ovate to narrowly obovate, entire, acute or obtuse, cuneate at base, sessile; lower smaller to scale-like.
Annual herb, 6–16 cm. tall when flowering, densely to more or less densely glandular-pilose.
Capsule (? immature) c. 7 x 7.5 mm., compressed subspherical, glabrous.
Flowers solitary in axils of upper leaves, pedicellate, ebracteolate.
Pedicels 3–7(10–17) mm. long, spreading, densely glandular-pilose.
Stems erect, simple (1)1.5–2.5 mm. in diam.