Herb, perennial, cespitose, rhizomatous. Culms trigonous, 25-50(-80) cm × 0.8-2.6 mm, glabrous. Leaves flat to V-shaped, 30-80 cm × 3-10 mm. Inflorescences: spikes ovoid, 1.5-3 × 1.5-3 cm; rays 4-7, 1-10 cm; 2d order rays occasionally present, 0.5-2 cm, rays often not elongate, inflorescence then capitate, 2-5 cm diam.; bracts 4-8, horizontal to ascending at 30°, flat to V-shaped, longest 6-35 cm × (1.5-)4-8 mm; rachilla persistent, wings 0.4-0.6 mm wide. Spikelets (10-)20-60, reddish brown, flattened elliptic in cross section, linear-lanceoloid, 6-22 cm × (1-)2-3(-4) mm; floral scales deciduous, 6-16, medially greenish, laterally reddish brown to brown, medially 3-5-ribbed, laterally 3-5-ribbed, ovate-lanceolate to ± orbiculate, 2.5-3 × 1.4-1.8 mm, apex acute to obtuse and mucronulate. Flowers: anthers 0.7-1.8 mm; styles (0.3-)1.2-2.8 cm; stigmas (1-)2-3 mm. Achenes brownish to black, stipitate or sessile, ellipsoid to obovoid or oblong, 1.3-2 × 0.75-1(-1.1) mm, apex obtuse, apiculate or not, surfaces coarsely punctate.

Fruiting throughout the year. Coral sand beaches, coastal rock outcrops; 0-10 m; Fla., Ga.; Mexico; West Indies; Central America (Belize, Honduras).