Sporobolus atrovirens (Kunth) Kunth

Sporobolus atrovirens (H.B.K.) Kunth, Rev. Gram. 1: 68
1829.
Vilfa atrovirens H.B.K. Nov. Gen. & Sp. 1: 138. 1815.
Agrostis atrovirens R. & S. Syst. Veg. 2: 361. 1817. (Based on Vilfa atrovirens H.B.K.)
Vilfa atrorubens H.B.K. Nov. Gen. & Sp. 7: pi. 685. 1825. (Error for atrovirens.)
Perennial; culms cespitose in rather small tufts, erect, glabrous, 1-2-noded, 10-30 cm. tall; sheaths glabrous; ligule very short, erose; blades flat or becoming loosely involute, especially at the slender point, glabrous, mostly in a basal tuft about 5 cm. long, 1-2 mm. wide, rarely 3 mm. ; panicles oblong, mostly dark-colored, open, 7-15 cm. long, rarely longer, mostly 4-6 cm. wide; the axis glabrous, the capillary branches often horizontal, naked at base, mostly solitary, somewhat distant, the lower with short ascending or spreading branches, the spikelets short-pediceled, appressed and closely set along the main branches and the lower branchlets; spikelets about 1 mm. long; glumes somewhat unequal, less than half as long as the spikelet, the first obtuse.
Type locality: El Penon, Valley of Mexico. Distribution: Rockv hills, central and southern Mexico.