Perennials, 10–25 (–50) cm tall, slender, caespitose to loosely caespitose; rhizome much branched, c. 1 mm in diam. Stem 0.5–1.0 mm in diam., erect to ascending, rarely rooting at nodes. Cataphylls 1 or absent, maroon or dark green, acute; basal leaves (0–) 1 (–2), 1–12.5 cm long. Cauline leaves 1–3, 1–12.5 cm long, terete, perfectly septate, unitubular, c. 1 mm in diam.; tip blunt to acuminate; sheaths 1–5 cm long; auricles 1.0–1.5 mm long, rounded, scarious. Lower bract leaf-like, terete, 1–5 cm long, usually shorter than, rarely slightly longer than the inflorescence, erect; other bracts green, lanceolate, 2.2–3.5 mm long. Inflorescence decompound, to 4× branched, of 3–50 heads, 2–8 (–15) × 4–10 cm, with ascending to spreading branches; heads obpyramidal, 2–10-flowered, 2–5 mm in diam. Tepals equal, lanceolate, green to stramineous, acute to acuminate, with short subulate apex, (1.8–) 2.0–2.3 (–2.8) mm long. Stamens 3, not exserted; anthers 0.4–0.5 mm long; filaments 0.5–1.1 mm long; style 0.1–0.2 mm long; stigmas 0.8–1 mm long. Capsules unilocular, narrowly ellipsoid to lanceolate in outline, sharply trigonous, acute, 2.8–4.2 mm long, stramineous, exceeding perianth. Seeds ovoid, 0.3–0.4 × 0.2–0.3 mm, yellowish brown, reticulate; appendages absent.