GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Eragrostis mexicana

HABIT Annual; caespitose. Culms geniculately ascending; 15–120 cm long. Culm-internodes eglandular, or glandular (below nodes). Leaf-sheaths eglandular, or glandular; pilose. Ligule a fringe of hairs. Leaf-blades lanceolate; 5–30 cm long; 3–10 mm wide; eglandular, or glandular (below). Leaf-blade surface glabrous, or pilose; hairy abaxially; with tubercle-based hairs.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; dense, or loose; 10–18 cm long; 4–8 cm wide. Primary panicle branches ascending, or spreading; 4–6 cm long. Panicle branches flexuous; eglandular, or glandular.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 7–15 fertile florets; with diminished florets at the apex. Spikelets ovate; laterally compressed; 6–9 mm long; 1.8–2 mm wide; breaking up at maturity; rhachilla persistent; retaining paleas.

GLUMES Glumes deciduous; similar; shorter than spikelet. Lower glume ovate; 1.6–1.8 mm long; 0.9 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 1.8–2 mm long; 0.9 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Fertile lemma ovate; 2–2.2 mm long; membranous; mid-green and red; mottled with last colour; keeled; 3 -veined. Lemma lateral veins prominent. Lemma apex acute. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FRUIT Caryopsis with adherent pericarp; 0.2–0.6 mm long.

DISTRIBUTION Africa: northeast tropical and south. Australasia: Australia. North America: northwest USA, north-central USA, northeast USA, southwest USA, south-central USA, southeast USA, and Mexico. South America: Mesoamericana, northern South America, western South America, Brazil, and southern South America.

NOTES Eragrostideae. Gr Texas 1993.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.