Perennial, the culms 15-60 cm tall, the underground part purplish. Leaves mostly basal, linear, to 4 (5.5) mm wide. Bracts subtending inflorescence long and leaflike; inflorescences of 5-15, simple, loosely cylindrical or flattened spikes; spikes sessile or on short rays, less than 7 cm long including rays; spikelets 5-7 (10) mm long, subterete, 3-8-flowered; scales having green median stripe, the margin broad and thin. Achenes subcylindric-trigonous, slightly curved, beaked at both ends, brownish, minutely papillose, 1.5-1.8 mm long. Croat 11866. Very abundant during part of the year in the Laboratory Clearing. May be found in flower throughout the year. Mexico to Brazil; West Indies; tropical Africa. In Panama, known from tropical moist forest in the Canal Zone, San Blas, Panama, and Darien, from tropical dry forest in Panama (Taboga Island), from premontane wet forest in Chiriqui and Coclé, and from lower montane wet forest in Chiriqui. See Fig. 53.