Perennials, c. (10–) 15–25 (–45) cm tall, densely (rarely loosely) caespitose; rhizome usually short, vertical; stolons absent. Leaves basal, (5–) 10–20 (–28) cm long, filiform to narrowly linear, often ±dilated (to 5 mm) and hyaline-bordered at base, otherwise 0.8–1.5 (–3.0) mm wide, slightly canaliculate to subinvolute; sheaths initially closed, later split, with apex acute; auricles absent. Stem leafless, ±smooth. Lower bract narrow, leaf-like, usually 2.5–7 cm long, longer or seldom shorter than inflorescence. Inflorescence usually subcongested, an irregular head of 1–10 subsessile clusters, often with 1–3 (–5) clusters or groups of clusters pedunculate; peduncles short, c. 0.5–3.0 cm long; clusters at first hemispherical, later subglobose, c. 0.7–1.1 cm wide (groups of clusters to 2 cm wide); upper bracts c. 3.5 mm long, subaristate, ±scabrid. Tepals ±unequal; outer tepals lanceolate, acuminate, subaristate, carinate, c. 3.0–3.5 mm long, with central band prominent, sometimes scabrid, rarely pale; inner tepals ovate-lanceolate, subobtuse, c. 2.7–3.0 mm long, with margins broad, membranous. Stamens 3–6; anthers 0.4–0.5 mm long; filaments 0.6–0.8 mm long; style c. 0.2 (–0.3) mm long; stigmas patent, recurved, to c. 1 mm long. Capsule 3-locular, trigonous ovoid to subglobose, ±obtuse to subacute, c. 2.2–2.6 mm long; mucro c. 0.1 mm long; capsule segments c. 1.4–1.6 mm wide, shiny, castaneous-brown to blackish brown, ±shorter than perianth. Seeds ovoid, pale brown, faintly transversely reticulate, c. 0.3–0.5 × 0.25–0.35 mm; apex whitish apiculate.