Rhynchospora alba (Linnaeus) Vahl var. macra C. B. Clarke ex Britton, Trans. New York Acad. Sci. 11: 88. 1892 (as Rynchospora); Phaeocephalum album (Linnaeus) House var. macrum (C. B. Clarke ex Britton) Farwell; Triodon albus Farwell var. macer (C. B. Clarke ex Britton) Farwell

Plants perennial, cespitose, 40–80 cm; rhizomes absent. Culms erect, trigonous, multiribbed, rather stiff. Principal leaves overtopped by culm; blades narrowly linear, proximally flat, (1.5–)2–3.5 mm wide, apex tapering, trigonous. Inflorescences: spikelet clusters 1–3, turbinate to hemispheric, 1.5–3 cm wide; subtending leafy bracts mostly exceeded by distal compound. Spikelets pale brown to nearly white, fusiform, 4–5(–7) mm, apex narrowly acute; fertile scales elliptic, 3.5–4 mm, apex narrowly acute, midrib excurrent as mucro. Flowers: perianth bristles (15–)18–20, reaching tubercle tip, retrorsely barbellate. Fruits 1 per spikelet, 2.5–3.2 mm; body brown with pale center, obovoid distal to short stipe, lenticular, 1.7–2.2 × 0.8–1.5, margins narrow, wirelike, flowing into tubercle edges; tubercle flat, narrowly triangular-subulate, 0.8–1 mm.

Fruiting late summer–fall. Sands and sandy peats of savanna bogs and seeps, pinelands; 0–200 m; Ala., Fla., Ga., La., Miss., N.C., S.C., Tex.; Central America (Nicaragua).