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 aristiglumis

HABIT Perennial. Butt sheaths persistent and investing base of culm; with fibrous dead sheaths. Culms erect; 30–50 cm long; 1.5–2 mm diam.; 3 -noded. Leaves mostly basal. Leaf-sheaths outer margin hairy. Ligule an eciliate membrane; 1.2–2 mm long. Leaf-blades conduplicate, or involute; 7–16 cm long; 2.5–4 mm wide; stiff. Leaf-blade surface scabrous; rough on both sides.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; erect; bilateral; 7–10 cm long; 6–9 mm wide. Rhachis flattened; puberulous on surface. Spikelet packing broadside to rhachis.

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

FERTILE SPIKELETS Spikelets comprising 3–4 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 8–11 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes pubescent.

GLUMES Glumes persistent; similar; subequal in width; shorter than spikelet. Lower glume lanceolate; 3.5–4.5 mm long; 1 length of upper glume; coriaceous; much thinner on margins; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex attenuate; awned; 1 -awned. Lower glume awn 4–5 mm long. Upper glume lanceolate; 3.5–4.5 mm long; 0.66 length of adjacent fertile lemma; coriaceous; with membranous margins; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex attenuate; awned; 1 -awned. Upper glume awn 4–5 mm long.

FLORETS Fertile lemma lanceolate; 6–7 mm long; chartaceous; keeled; 5 -veined. Lemma surface glabrous. Lemma margins pubescent. Lemma apex acuminate; mucronate, or awned; 1 -awned. Principal lemma awn 1 mm long overall. Palea 1 length of lemma; 2 -veined; 2-keeled. Palea keels ciliate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 4 mm long; yellow.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Asia-temperate: China.

NOTES Triticeae. Fl China 2005.

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