Annual, usually with many branches. Stems 15-30 cm with spreading short hairs. Leaves linear to linear lanceolate, weakly crenate to subentire at margins, cuneate above and below; up to 5 x 1.5 cm with adpressed hairs on upper surface and a denser indumentum of short spreading hairs below especially on nerves; petiole subabsent to c. 5 mm on lower leaves. Verticiltasters globose in uppermost leaf axils, 1-4, c. 2.5 cm in diameter, c. 16-20-flowered. Bracts narrow linear, c. 1/2 length of calyces, long-ciliate at margins. Calyx 7-9 mm, scarcely elongating in fruit, pale green, scarcely curved, with a prominently oblique mouth; teeth 8-10, irregular in size, triangular, 2-3 mm long with short spinulose apices. Corolla 8-10 mm white; upper lip short, densely bearded; lower lip dearly longer than upper and projecting forward. Nutlets bluntly trigonous, c. 2.5 x 1.5 mm.