Rhizome rather long, creeping or obliquely ascending. Culms densely tufted, 10-15 cm tall, nearly half-terete, smooth, several brown and old leaves and sheaths usually disintegrating into fibers. Leaves shorter than culm, not up to 1 mm wide, usually involute into needle-shape, smooth, brown and membranous sheathed. Involucral bracts scale-shaped, lanceolate, long aristate at apex, longer than or slightly shorter than spike, not sheathed. Spikes 2-4, congregate at top of culm; terminal spike male, narrowly lanceolate, 8-15 mm, sessile; lateral spikes female, ovate, 5-8(-10) mm, densely several flowered, subsessile. Female glumes dark brown, ovate, 3.5-4 mm, membranous, with 1-veined yellowish costa, hyaline on upper margin, apex acute, mucronate. Utricles dark brown, suberect or slightly obliquely patent, shorter than or equaling glume, ovate, obtusely trigonous, 3.5-4 mm, thinly leathery, shiny, indistinctly veined, base cuneate, shortly stipitate, apex abruptly contracted into a short beak, orifice very shortly 2-toothed. Nutlets brownish yellow, subelliptic, trigonous, ca. 2 mm, sessile, apex mucronate; style short, base slightly thickened; stigmas 3. Fl. and fr. Jun-Aug.