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 marginatus

HABIT Perennial; caespitose; clumped loosely. Culms 50–100 cm long. Culm-nodes brown. Leaf-sheaths reticulately veined; puberulous. Leaf-sheath auricles absent, or falcate. Ligule an eciliate membrane; 0.2–0.5 mm long; truncate. Leaf-blades 10–25 cm long; 4–8 mm wide. Leaf-blade midrib prominent beneath. Leaf-blade surface ribbed; glabrous. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence composed of racemes. Peduncle glabrous, or pubescent above.

Racemes 1; single; bilateral; 10–30 cm long. Rhachis angular, or semiterete; scabrous on margins. Spikelet packing broadside to rhachis; lax. Rhachis internodes linear. Rhachis internode tip flat.

Spikelets solitary. Fertile spikelets sessile, or pedicelled.

FERTILE SPIKELETS Spikelets comprising 3–7 fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 20–30 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes pubescent.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 7 mm long; 0.75 length of upper glume; coriaceous; much thinner on margins; without keels; 5–6 -veined. Lower glume apex attenuate; mucronate, or awned; 1 -awned. Lower glume awn 0.6–6 mm long. Upper glume lanceolate; 9 mm long; 0.75 length of adjacent fertile lemma; coriaceous; with scarious margins; without keels; 6 -veined. Upper glume apex attenuate; mucronate, or awned; 1 -awned. Upper glume awn 0.5–6 mm long.

FLORETS Fertile lemma lanceolate; 12–13 mm long; coriaceous; 5 -veined. Lemma margins scabrous. Lemma apex acute; awned; 1 -awned. Principal lemma awn 10–15 mm long overall. Palea 1 length of lemma. Palea keels scabrous. Palea surface scabrous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 6–8 mm long; yellow. Stigmas 2. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp; linear, or oblong; sulcate on hilar side; 8–9 mm long; hairy at apex. Embryo 0.15 length of caryopsis. Hilum linear; 1 length of caryopsis.

DISTRIBUTION Africa: north.

NOTES Triticeae. Fl Afr N 1994.

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