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 lehmanniana

HABIT Perennial; caespitose; clumped densely. Basal innovations flabellate. Culms geniculately ascending; 70–170 cm long; 2 mm diam.; 3–4 -noded. Culm-internodes distally glabrous. Lateral branches lacking. Leaves mostly basal. Leaf-sheaths keeled. Ligule an eciliate membrane. Leaf-blades persistent, or deciduous at the ligule; conduplicate; 40–70 cm long; 1–4 mm wide; coriaceous; stiff. Leaf-blade midrib keeled beneath. Leaf-blade surface scabrous. Leaf-blade apex attenuate; filiform.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong, or ovate; 20–40 cm long; 5–10 cm wide; contracted about primary branches. Primary panicle branches appressed, or ascending, or spreading.

Spikelets appressed; solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 2.5–3 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent; disarticulating obliquely.

GLUMES Glumes persistent; similar; reaching apex of florets, or exceeding apex of florets. Lower glume lanceolate; 2.5–3 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume surface smooth, or asperulous. Lower glume apex emarginate, or obtuse; muticous, or mucronate. Upper glume lanceolate; 2.5–3 mm long; 1–1.1 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume surface smooth, or asperulous. Upper glume apex emarginate, or obtuse; muticous, or mucronate.

FLORETS Fertile lemma lanceolate; 2.4–3 mm long; membranous; without keel; 3 -veined. Lemma lateral veins excurrent. Lemma surface scabrous. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn flexuous; 20–30 mm long overall. Palea 1 length of lemma; 2 -veined.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 1.5–1.7 mm long; purple.

FRUIT Caryopsis with adherent pericarp; fusiform.

DISTRIBUTION South America: Mesoamericana, northern South America, and western South America.

NOTES Eragrostideae. Fl Costa Rica 1994.

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