Plants annual (or short-lived perennial), not rhizomatous. Stems prostrate or ascending, branched, angled or grooved, 13–19 cm, retrorsely pubescent in 2 lines. Leaves petiolate; petiole 1–4 mm; blade 3(–7)-veined, ovate to broadly ovate, 5–18 × 4–8 mm, margins ciliate, apex acute. Inflorescences 3–10(–15)-flowered; bracts 1–15 mm, proximal foliaceous, distal much smaller, scarious. Pedicels ascending to erect, recurved in fruit, 4–15(–22) mm. Flowers: sepals 4 or 5, midrib keeled, ovate-lanceolate, 2–4 mm, margins broad, apex acuminate; petals 4 or 5, ca. 1.3 mm, ca. 1/2 as long as sepals. Capsules ovoid, 2–2.5 mm, shorter than sepals. Seeds reniform, 1 mm, smooth. 2n = 24 (Europe).