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.

Festuca yalaensis

HABIT Perennial. Rhizomes elongated. Stolons present. Basal innovations extravaginal. Culms 50–120 cm long; 0.7–1.5 mm diam.; (3–)4–5 -noded. Culm-internodes smooth. Leaf-sheaths open for most of their length; antrorsely scabrous. Ligule a ciliolate membrane; 0.2–0.6 mm long. Leaf-blades erect; filiform, or linear; conduplicate, or involute; 15–40 cm long; 0.8–2 mm wide; 6–18 cm long at summit of culm. Leaf-blade venation comprising 5 vascular bundles; with 4 inner ridges; with sclerenchyma strands below veins and above all veins. Leaf-blade surface scabrous; rough abaxially; puberulous; hairy abaxially.

INFLORESCENCE Inflorescence a panicle; comprising 30–80 fertile spikelets. Peduncle smooth, or antrorsely scabrous above.

Panicle open; lanceolate; 8–17 cm long; 1–2.5 cm wide. Primary panicle branches 4–7 in number; 2–3 -nate; 4 cm long; with lower 0.5 length of panicle. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising (2–)3–5(–7) fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; (5–)6–9.5(–11.5) mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes scaberulous. Floret callus pubescent; obtuse.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; (1.8–)2.8–3.8 mm long; 0.75 length of upper glume; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; (3–)3.8–4.8 mm long; 0.75–0.8 length of adjacent fertile lemma; membranous; without keels; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 4.5–6.3 mm long; chartaceous; without keel; 5 -veined. Lemma surface scaberulous; rough on veins. Lemma apex acuminate; muticous, or mucronate. Palea 1 length of lemma. Palea keels puberulous; adorned above; with 0.5 of their length adorned. Palea surface puberulous; hairy on back and on margins; hairy above. Palea apex dentate; 2 -fid. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 2.2–3 mm long. Ovary with a few apical hairs.

DISTRIBUTION Pacific: north-central.

NOTES Poeae. Mull. & Catalan.

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