8. 'Eleocharis' R. Brown, Prodr., 224. 1810

Herbs, annual or perennial, usually cespitose, often rhizomatous, sometimes stoloniferous; rhizomes rarely with terminal tubers or bulbs, horizontal and long or ascending and caudexlike. Cu1ms sometimes solitary, terete, 3-5-angled or more, or strongly compressed in cross section, spongy with internal air cavities and incomplete transverse septa or sometimes hollow with complete transverse septa. Leaves basal, 2 per culm; ligules absent; blades absent or a mucro or awn (tooth) at apex of sheath, very rarely flattened, to 6 cm. Inflorescences terminal; spikelet 1; involucral bracts absent, rarely a proximal scale of spikelet resembling short bract. Spikelets: scales 4-500 or more, spirally or rarely distichously arranged, each subtending flower or proximal 1-2(-3) empty, stramineous (straw-brown) to medium brown or red brown or blackish brown. Flowers bisexual; perianth of (0–)3-6(-10) bristles, straight or curved, shorter than to 2 times longer than achene, retrorsely (to antrorsely) spinulose or sometimes smooth; stamens 1-3; styles linear, 2-3-fid, base (tubercle) usually persistent, usually enlarged, usually different in appearance from achene. Achenes biconvex, piano-convex, or trigonous to subterete.