Prostrate or weakly ascending, often pink-stemmed annual, stems to c. 20 cm long, simple or few-branched. Leaves often ± rosetted at base, often absent from stems, oblong to narrowly elliptic, the largest 1–5 cm long, 2–8 mm wide, subsessile, glabrous. Cymes elongating, mostly 3–7-flowered; bracts opposite; pedicels 6–12 mm long at anthesis, elongating to 2.5 cm or more and slightly to strongly reflexing in fruit; sepals very broadly ovate, 2–3.5 mm long, obtuse (rarely shortly apiculate), persistent; petals 5, 3–7 mm long, white to deep pink; stamens 7–20; style trifid to base. Capsule ovoid, 3.5–4.5 mm long, pale, splitting almost to base into 3 valves; seeds numerous (more than 30), reniform, c. 0.5 mm long, shining, dark red-brown or greyish, colliculate. Flowers Aug.–Oct.