Rhynchospora capillacea Torr.

Plants perennial, cespitose, 10–40 cm, wiry; rhizomes stoloniferous, slender, to 1.5 mm thick. Culms erect or curved, leafy, filiform, angularly few ribbed. Leaves ascending-excurved, overtopped by culm; blades filiform, involute, apex setaceous. Inflorescences: spikelet clusters 1–2(–3), often sparse, ellipsoid or narrowly turbinate, less than 1 cm wide; subtending foliaceous bracts exceeding compounds. Spikelets erect or ascending, pale red brown to brown, fusiform, 6–7 mm; fertile scales elliptic, 4 mm, apex rounded or acute, midrib short excurrent or not. Flowers: perianth bristles 6, overtopping tubercle base, mostly retrorsely barbellate, sometimes smooth [forma laeviseta (E. J. Hill) Fernald]. Fruits 1–4(–5) per spikelet, 2.5–3 mm; body pale brown, slender stipitate, ellipsoid, lenticular, 1.5–2 × 0.8–1 mm; surfaces longitudinally minutely striate, obscurely transversely low rugose, dotted; tubercle narrowly triangular subulate, flattened, 0.8–1.7 mm.