GrassBase - The Online World Grass Flora

Descriptions

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

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

Muhlenbergia minutissima

HABIT Annual; caespitose; clumped densely. Culms geniculately ascending; weak; 5–40 cm long. Culm-internodes distally hirsute. Ligule an eciliate membrane; 1–3 mm long; hyaline; lacerate. Leaf-blades flat, or involute; 2–6 cm long; 1 mm wide. Leaf-blade surface scabrous; glabrous, or hirsute.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong; effuse; 10–20(–40) cm long; 0.66–0.75 of culm length.

Spikelets spreading; solitary. Fertile spikelets pedicelled. Pedicels filiform; 2–5 mm long.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 1.2–1.8 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet; similar to fertile lemma in texture. Lower glume elliptic; 0.5–1 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface pilose. Lower glume apex obtuse, or acute. Upper glume elliptic; 0.5–1 mm long; 0.4–0.6 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume surface pilose. Upper glume apex obtuse, or acute.

FLORETS Fertile lemma lanceolate; 1.2–1.8 mm long; membranous; keeled; 3 -veined. Lemma midvein pubescent; hairy below. Lemma margins pubescent; hairy below. Lemma apex emarginate to obtuse; muticous, or mucronate. Palea 1 length of lemma; 2 -veined. Palea apex obtuse.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 0.3–0.5 mm long.

FRUIT Caryopsis with adherent pericarp; fusiform; 0.6–1 mm long.

DISTRIBUTION North America: northwest USA, southwest USA, south-central USA, and Mexico. South America: Mesoamericana.

NOTES Eragrostideae. Gould.

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