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.

Leymus mundus

HABIT Perennial; caespitose. Rhizomes elongated. Butt sheaths persistent and investing base of culm; with compacted dead sheaths, or fibrous dead sheaths. Culms erect; 25–55 cm long; 1.5–2.1 mm diam.; 3–4 -noded. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; 1–1.6 mm long; obtuse. Leaf-blades involute; 3–21 cm long; 2.5–4 mm wide; coriaceous; stiff. Leaf-blade surface scabrous; rough adaxially.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; erect; linear; bilateral; 4–10 cm long; 8–10 mm wide. Rhachis scabrous on surface; ciliate on margins. Spikelet packing broadside to rhachis; crowded; with subequal internodes, or lowest internode elongated. Rhachis internodes 4–5 mm long.

Spikelets in pairs, or in threes. Fertile spikelets sessile; 2–3 in the cluster.

FERTILE SPIKELETS Spikelets comprising 4–5 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 10–15 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 0.5–1 mm long; scaberulous.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 8–10 mm long; 1 length of upper glume; much thinner on margins; 1-keeled; 1–3 -veined. Lower glume lateral veins absent, or obscure. Lower glume margins eciliate, or ciliolate. Lower glume apex setaceously attenuate. Upper glume lanceolate; 8–10 mm long; 1–1.1 length of adjacent fertile lemma; with membranous margins; 1-keeled; 1–3 -veined. Upper glume lateral veins absent, or obscure. Upper glume margins eciliate, or ciliolate. Upper glume apex setaceously attenuate.

FLORETS Fertile lemma lanceolate; 8–9 mm long; coriaceous; much thinner on margins; without keel; 7 -veined. Lemma margins without distinctive roughness, or scaberulous. Lemma apex acuminate. Palea 2 -veined. Palea keels smooth. Palea apex emarginate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 3 mm long. Ovary pubescent on apex.

DISTRIBUTION Asia-temperate: China.

NOTES Triticeae. Cai & Su 2009.

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