Plants annual, tufted, often mat-forming, often stoloniferous, sometimes entirely vegetative; rhizomes absent. Culms erect, ascending or arching, quadrangular, sulcate, 1–13 cm × 0.1–0.3 mm, soft. Leaves: distal leaf sheaths persistent or disintegrating, red-brown, stramineous, green, or mottled red-brown, translucent, apex narrowly acute. Spikelets: basal spikelets often present, bisexual; often proliferous, ovoid or ellipsoid, laterally compressed when young, but terete at maturity, 2–7 × 1–2.6 mm, acute; proximal scale empty, often persistent, amplexicaulous, similar to floral scales; subproximal scale with a flower; floral scales spirodistichous (superficially appearing ± spiraled), (4–)10–28, 6–9 per mm of rachilla, pale brown, mottled red-brown to purple, ovate or elliptic, 1.3–2.1 × 0.7–1 mm, membranous, midribs green and red-brown, prominent, apex rounded to obtuse. Flowers: perianth bristles 6, colorless, white, or stramineous, slightly shorter than to equaling achene, spinules retrorse, acute; stamens 3; anthers 0.4–0.5 mm; styles 3-fid. Achenes greenish or pale brown or red-brown, often clearly spotted greenish or red-brown, ellipsoid to obovoid, trigonous (or terete?), angles prominent (keeled), 0.6–0.8 × 0.4–0.5 mm, apex constricted proximal to tubercle, smooth. Tubercles red-brown, pyramidal, trigonous, 0.1–0.3 × 0.2–0.4 mm.
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Dwarf annual, the capillary culms 3-7 cm. high; spikelets 2-4 mm. long, ovate, usually many-flowered, the scales acute, dark brown; bristles inconspicuous, shorter than the achene, which is ovate, sharply trigonous, pale brown to olive, the tubercle trigonous.
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