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.

Leptochloa dubia

HABIT Perennial; caespitose. Butt sheaths glabrous, or pilose. Basal innovations flabellate. Culms 30–110 cm long; wiry. Lateral branches lacking. Leaf-sheaths glabrous on surface. Ligule a ciliolate membrane; 0.5–1.5 mm long. Leaf-blades flat, or involute; 5–30 cm long; 2–8 mm wide; glaucous. Leaf-blade surface glabrous, or pilose; sparsely hairy.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2–15; borne along a central axis; ascending, or spreading; flexuous; unilateral; 4–12 cm long. Central inflorescence axis 5–20 cm long. Rhachis semiterete. Spikelet packing broadside to rhachis; regular; 2 -rowed.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 3–8 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 5–10 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 3.5–4.5 mm long; 0.9 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 4–5 mm long; 1–1.1 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Fertile lemma oblong; 3.5–5 mm long; membranous; keeled; 3 -veined. Lemma lateral veins close to margins. Lemma margins eciliate, or pubescent. Lemma apex emarginate; muticous, or mucronate. Palea 2 -veined. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 1.5 mm long.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION North America: north-central USA, southwest USA, south-central USA, southeast USA, and Mexico. South America: Mesoamericana, western South America, Brazil, and southern South America.

NOTES Eragrostideae. Gr Texas 1994.

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