GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Elymus tridentatus

HABIT Perennial; caespitose. Culms erect, or geniculately ascending; 42–65 cm long; 1.5–2 mm diam.; 2–3 -noded. Culm-internodes smooth; distally glabrous. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; 0.5 mm long; truncate. Leaf-blades involute; 5–7 cm long; 2 mm wide. Leaf-blade surface pubescent; hairy adaxially.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; straight; bilateral; 5–11.5 cm long; 5 mm wide; bearing 6–14 fertile spikelets on each. Rhachis flattened; glabrous on surface. Spikelet packing broadside to rhachis.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 4–5 fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 10–13 mm long; 2 mm wide; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1.5–2 mm long; pubescent. Floret callus pubescent.

GLUMES Glumes persistent; similar. Lower glume oblong; 4–5 mm long; coriaceous; without keels; 3 -veined. Lower glume surface smooth, or asperulous; rough on veins. Lower glume apex obtuse. Upper glume oblong; 5–6.5 mm long; coriaceous; without keels; 3 -veined. Upper glume surface smooth, or asperulous; rough on veins. Upper glume apex obtuse.

FLORETS Fertile lemma oblong; 7–9 mm long; coriaceous; 5 -veined. Lemma surface pubescent; hairy below. Lemma margins pubescent. Lemma apex dentate; 3 -fid; with lobes 0.5–1 mm long; acuminate; muticous. Palea 1 length of lemma; 2 -veined. Palea keels ciliate; adorned above; with 0.33–0.5 of their length adorned. Palea surface scabrous. Palea apex truncate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 2 mm long; black.

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.