Glabrous herb with thick creeping succulent stem, which roots at the nodes, up to 50 cm. long; branches erect or ascending, ± 7–30 cm. tall, often reddish. Leaves opposite, subsessile or shortly petiolate; blade oblong-lanceolate or lanceolate, 1.3–5 cm. long, (0.4–)0.75–2.5 cm. wide, acute or obtuse at both ends, finely serrulate, the teeth reddish; petiole 1–5 mm. long; stipules ovate-triangular, 2–4 mm. long, acute or acuminate, membranous, dentate. Flowers 5-merous, many in dense clusters; pedicels 0.5–3 mm. long. Sepals lanceolate to broadly elliptic, 1–2 mm. long, acuminate or mucronulate, green tipped with red. Petals at first erect, later spreading or recurved, oblong, lanceolate or subspathulate, slightly longer than the sepals, 1–2.2 mm. long, 0.5–0.6 mm. wide, white or pink, transparent. Stamens 10; filaments thin, filiform, slightly widened at the base. Ovary subglobose; styles recurved, 0.25–0.3 mm. long. Capsule crimson, subglobose, 2.5 mm. in diameter, with 5 longitudinal furrows. Seeds oblong-ellipsoid, often curved, brown, shining, ± 0.5 mm. long, strongly reticulate. Fig. 1/1–7.