Trisetum tonduzii Hitchc.

Trisetum tonduzii Hitchcock, sp. nov
Perennial, with creeping rhizomes; culms erect, cespitose, glabrous, 2-noded or 3-noded near the base, 30-40 cm. tall, sometimes taller; sheaths glabrous; ligule truncate or rounded, dentate, about 1 mm. long, the margin of the sheath on one side extending upward as an auricle as long as the ligule; blades mostly basal, erect, rather stiff, glabrous, loosely involute, ending in a slender point, 5-15 cm. long, 2-3 mm. wide; panicle ovate-pyramidal, open, purplish, 5-15 cm. long, sometimes nearly as wide, the axis glabrous, the branches slender, verticillate, spreading, glabrous, naked below, the verticils mostly 2-3 cm. apart, the branchlets short and somewhat appressed along the upper part of the branches, the shorter pedicels 1-2 mm. long; spikelets 2-flowered, 4—5 mm. long; the rachilla villous, the hairs at the summit as much as 2 mm. long, the callus-hairs also about 2 mm. long; glumes rather broad, equal in length, nearly equal in width, glabrous even on the keel, acute, about 4 mm. long; lemmas scaberulous, 4-4.5 mm. long, the neres excurrent as 4 short slender teeth; awn attached a little above the middle, very slightly scabrous, curved or loosely spiral at base and sharply spreading horizontally, 5-8 mm. long.
Planta perennis, rhizomata; culmi erecti, glabri, 30-40 cm. alti; vaginae glabrae; ligula truncata, dentata, 1 mm. longa; laminae glabrae, plerumque paullum involutae, 2-3 mm. latae, apice attenuatae; panicula pyramidalis, patens, 5-15 cm. longa, ramis verticillatis, patulis, glabris, inferne nudis; spiculae 2-florae, 4-5 mm. longae, pilis rachiUae et calli 2 mm. longis; glumae equales, glabrae, acutae, 4 mm. longae; lemmata scaberula, 4-4.5 mm. longa, apice quadriseta, paullum supra medium aristata, arista geniculata, inferne laxe torta, superne patula, 5-S mm. longa.
Type collected in pastures on Mount PoSs, Costa Rica, altitude 2460 meters, November 1896, A. Tonduz, Herb. Inst. Phys.-geogr. Costa Rica no. 10749 (U. S. Nat. Herb. no. 358711).
Distribution: Open grassland, high mountains of Costa Rica.

Trisetum tonduzii là một loài thực vật có hoa trong họ Hòa thảo. Loài này được Hitchc. miêu tả khoa học đầu tiên năm 1939.