Perennials, loosely caespitose; rhizome stout, creeping, with internodes short, to 1–2 cm long; stems in rows, usually 25–40 (–60) cm long, c. 1.5 mm in diam. Cataphylls 2 (–3), loose, pale brown; sheaths obtuse; blade setiform, usually 2–4 mm; cauline leaf usually single; auricles short, obtuse. Leaves of sterile shoots single, cauliform, terete, equalling to much exceeding stems, c. 2 mm in diam., ±smooth to slightly striate; tip acute to subobtuse. Bracteoles 2, membranous, broadly ovate, obtuse, usually 2–4 mm long. Tepals linear-lanceolate, pale stramineous to scarious, irregularly unequal; outer tepals usually 3.2–4.0 cm long; inner tepals c. 2.0–2.5 (–3.5) cm long. Stamens 6, much shorter than perianth, usually 10–11 mm long. Anthers 8–10 mm long; pollen sacs slightly overtopping connective; tips later erecto-patent and hence anthers bicorniculate at apex. Filaments to c. 2 mm long. Style c. 5–6 mm long; stigmas 8–10 mm long. Capsule oblong-ellipsoidal, ±trigonous, acuminate, usually 1.7–2.2 (–2.5) cm long, pale brown, shining. Seeds pale brown, ±ellipsoidal, with body c. 1.0 mm long, 0.4–0.5 mm wide, or 5.0–6.5 mm long including the two whitish subequal tail-like appendages each 1.7–2.4 mm long.