Cyperus dentoniae

Herbs, perennial, cespitose, shortly rhizomatous. Culms 1-4, trigonous, (2-)20-50(-80) cm × (0.8-)1.5-2(-2.8) mm, basally glabrous or nearly so, apically hispidulous, on faces and angles distally, especially so immediately proximal to bracts. Leaves 2-5(-7), V-shaped, (5-)15-30(-45) cm × (1.5-)2.5-5(-8) mm. Inflorescences: spike 1 (occasionally 1-2 smaller sessile spikes at base), densely cylindric, (7-)11-20(-25) × (5-) 7-10(-12) mm; rays 3-6(-10), (1-)3-6(-18) cm, rays and rachis hispidulous; bracts 4-8(-10), ascending at 30-60°, V-shaped, (2-)10-25(-45) cm × (1-)3-6(-8) mm; rachilla deciduous, wings persistent, 0.3-0.4 mm wide. Spikelets (20-)70-120(-140), oblong-ellipsoid to oblong-lanceoloid, ± terete to quadrangular, (2.2-)3.4-4.5(-5.6) × (0.8-)0.9-1.2(-1.3) mm; distal spikelet spreading or ascending; floral scales 1(-3), appressed, stramineous, red-spotted, strongly 3(-4)-ribbed on either side of green part, medially weakly 3-ribbed, ovate to elliptic ovate, (2.4-)2.8-3.3(-3.6) × 1.6-2 mm, apex acute, mucronulate from excurrent midrib. Flowers: anthers (0.3-)0.4-0.6 mm; styles 0.4-0.6(-0.8) mm; stigmas 1-1.4 mm. Achenes brown, stipitate, ellipsoid, (1.6-)1.8-2 × (0.7-) 0.8-0.9 mm, stipe 0.1-0.2 × 0.2 mm, apex ± truncate, apiculate, surfaces puncticulate to glabrous.

Fruiting mid summer-fall (Jul-Sep). Various dry, open environments; 500-1000 m; Ariz.; Mexico; Central America; South America.