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.

Elymus laxistachyus

HABIT Perennial; caespitose; clumped densely. Culms erect; 25–55 cm long; 2–3 -noded. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; 0.3 mm long; truncate. Leaf-blades involute; 5–8 cm long. Leaf-blade surface glabrous, or puberulous; hairy adaxially.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; straight, or arcuate; bilateral; 5–7 cm long; 5 mm wide. Rhachis flattened; puberulous on surface. Spikelet packing broadside to rhachis. Rhachis internodes 5–9 mm long.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 3–5 fertile florets; with diminished florets at the apex. Spikelets elliptic to oblong; laterally compressed; 10–12 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar. Lower glume lanceolate, or oblong; 5–7 mm long; coriaceous; much thinner on margins; without keels; 2–4 -veined. Lower glume apex acuminate. Upper glume lanceolate, or oblong; 6–8 mm long; coriaceous; with membranous margins; without keels; 2–4 -veined. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn 6–8 mm long.

FLORETS Fertile lemma lanceolate, or oblong; 7–8 mm long; coriaceous; 5 -veined. Lemma surface villous. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn 2–3 mm long overall. Palea 0.9 length of lemma; 2 -veined. Palea keels scabrous. Palea surface glabrous. Palea apex truncate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 2–2.5 mm long.

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.