Festuca riloensis

HABIT Perennial; caespitose. Butt sheaths persistent and investing base of culm. Basal innovations intravaginal. Culms 10–20 cm long. Leaf-sheaths tubular for much of their length; with 0.66 of their length closed; with flat margins; glabrous on surface. Leaf-sheath auricles erect. Ligule an eciliate membrane. Leaf-blades filiform; conduplicate; 0.5–0.8 mm wide. Leaf-blade venation comprising 7 vascular bundles; with 3 inner ridges; with 3 subepidermal sclerenchyma strands; with subepidermal sclerenchyma free from veins; without layer of subepidermal sclerenchyma masking vein striation. Leaf-blade surface smooth.

INFLORESCENCE Inflorescence a panicle.

Panicle open; 1–3.5 cm long. Primary panicle branches simple; bearing 1–2 fertile spikelets on each lower branch.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets with diminished florets at the apex. Spikelets oblong; laterally compressed; 6.5–8.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes obscured by lemmas.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; chartaceous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 2.9–3.6 mm long; 0.75 length of adjacent fertile lemma; chartaceous; without keels; 3 -veined. Upper glume apex acuminate.

FLORETS Fertile lemma oblong; 4.1–4.7 mm long; chartaceous; purple; without keel; 5 -veined. Lemma surface scabrous; rough above. Lemma apex acute; awned; 1 -awned. Principal lemma awn 2.1–2.7 mm long overall. Palea 2 -veined. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 2–2.5 mm long.

FRUIT Caryopsis with adherent pericarp; ellipsoid. Hilum linear. Disseminule comprising a caryopsis and palea.

DISTRIBUTION Europe: southeastern.

NOTES Poeae. Fl Eur 1995.

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