Poa calycina var. mathewsii (Ball) Refulio

Dissanthelium sclerochloides Fourn. Mex. PI. Gram. 112. 1886
Perennial; culms densely tufted, glabrous, mostly less than 10 cm. tall; sheaths glabrous, loose, somewhat compressed-keeled, striate-nerved; ligule truncate or rounded, dentate, about I mm. long, the thin margins of the sheath extending upward into a shoulder or short auricle; blades numerous, pale, cartilaginous, folded or involute, sulcate (at least when dry), glabrous, 1-1.5 mm. wide when flattened out, mostly less than 5 cm. long, the margins very minutely scabrous, the tips abruptly acute or boat-shaped; panicle pale or purplish, dense, ovoid, 1-1.5 cm. long, the axis glabrous, the branches appressed, bearing 1-3 spikelets, minutely puberulent below the spikelets; spikelets 2-flowered, the rachilla between the florets very short; glumes equal, glabrous (even the keel), cartilaginous, broad, acute, 3.5 mm. long, the first 1-nerved, the second rather obscurely 5-nerved; lemmas very minutely scabrous, especially the second, obscurely nerved, ovate-lanceolate, the first 2.5 mm. long, about 1 mm. wide, the second a little shorter and narrower; anthers 1 mm. long.
Type locality: Mexico (cited specimens, Nevada de Toluca, Hahn, San Luis Potosi, Virlet 1434).
Distribution: Alpine regions of high mountains, Mexico (Ixtaccihuatl, Purpus 1633, Nevada de Toluca, Pringle 4222).