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 altus

HABIT Perennial; culms solitary, or caespitose; clumped loosely. Culms erect; 80–150 cm long; 2 -noded. Culm-internodes glaucous; smooth; distally glabrous. Leaves mostly basal. Leaf-sheaths smooth; glabrous on surface. Ligule an eciliate membrane; 2 mm long. Leaf-blades flat, or involute; 4–5 mm wide; stiff. Leaf-blade surface scabrous; rough adaxially.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; erect; bilateral; 8–15 cm long; 7–9 mm wide. Rhachis flattened; puberulous on surface. Spikelet packing broadside to rhachis. Rhachis internodes 5–30 mm long.

Spikelets in pairs, or in threes. Fertile spikelets sessile; (1–)2–3 in the cluster.

FERTILE SPIKELETS Spikelets comprising 4–6 fertile florets; with diminished florets at the apex. Spikelets elliptic; laterally compressed; 15–18 mm long; breaking up at maturity; disarticulating below each fertile floret. Spikelet callus pilose. Rhachilla internodes 1.5–2 mm long; pubescent. Floret callus pilose. Floret callus hairs 1 mm long.

GLUMES Glumes persistent; similar; subequal in width; shorter than spikelet. Lower glume linear; 10–15 mm long; 0.9 length of upper glume; coriaceous; much thinner on margins; 1-keeled; 3 -veined. Lower glume lateral veins obscure. Lower glume margins ciliate. Lower glume apex acuminate to setaceously attenuate. Upper glume linear; 10–15 mm long; 1 length of adjacent fertile lemma; coriaceous; with membranous margins; 1-keeled; 3 -veined. Upper glume lateral veins obscure. Upper glume margins ciliate. Upper glume apex attenuate, or setaceously attenuate.

FLORETS Fertile lemma lanceolate; 10–14 mm long; chartaceous; keeled; 5 -veined. Lemma surface puberulous. Lemma margins ciliate. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn 1–3 mm long overall. Palea 1 length of lemma; 2 -veined; 2-keeled. Palea keels ciliate; adorned above. Palea apex emarginate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 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.