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 jaime-hintonii

HABIT Perennial; caespitose; clumped loosely. Rhizomes short. Basal innovations extravaginal. Culms erect; 44–82 cm long. Culm-internodes elliptical in section; distally pubescent. Culm-nodes glabrous, or pubescent. Leaf-sheaths 6–28 cm long; longer than adjacent culm internode; glabrous on surface, or puberulous. Ligule a ciliolate membrane; 0.4–1 mm long; truncate. Leaf-blades flat, or conduplicate; 5–22 cm long; 1.8–5 mm wide. Leaf-blade surface pubescent; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; lanceolate; 3–34 cm long; 0.7–7 cm wide; contracted about primary branches. Primary panicle branches ascending; 0.5–6.5 cm long; bearing spikelets almost to the base.

Spikelets appressed; solitary. Fertile spikelets pedicelled. Pedicels 0.5–2 mm long; scaberulous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets elliptic; laterally compressed; 1.5–2.1 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 oblong; 0.7–1.2 mm long; 1 length of upper glume; membranous; without keels; 1 -veined. Lower glume lateral veins obscure. Lower glume apex entire, or erose; obtuse, or acute. Upper glume oblong; 0.7–1.2 mm long; 0.5 length of adjacent fertile lemma; membranous; without keels; 1 -veined. Upper glume primary vein scaberulous. Upper glume lateral veins absent. Upper glume apex entire, or erose; obtuse, or acute.

FLORETS Fertile lemma elliptic, or oblong; 1.5–2 mm long; membranous; without keel; 3 -veined. Lemma midvein pubescent. Lemma lateral veins obscure. Lemma surface pubescent; hairy below. Lemma margins pubescent. Lemma hairs 0.2–0.5 mm long. Palea oblong; 1.5–2 mm long; 2 -veined. Palea surface pubescent; hairy on back and on flanks; hairy below. Palea apex obtuse, or acute.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 0.8–1 mm long.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION North America: Mexico.

NOTES Eragrostideae. Peterson 2000.

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