Festuca argentina

HABIT Perennial; caespitose. Butt sheaths pallid, or yellow; pubescent. Basal innovations intravaginal. Culms erect; 40–100 cm long. Lateral branches lacking. Leaf-sheaths open for most of their length; glabrous on surface. Ligule a ciliolate membrane; 0.5 mm long. Leaf-blades filiform; conduplicate; 15–30 cm long; 1–1.5 mm wide; stiff. Leaf-blade surface puberulous; hairy adaxially. Leaf-blade apex pungent.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear; 7–15 cm long. Panicle axis scaberulous. Panicle branches scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 4–7 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 10–15 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1–1.5 mm long; smooth, or scaberulous. Floret callus pubescent.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 5–7.5 mm long; 0.75 length of upper glume; chartaceous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 6–8 mm long; 0.7–0.8 length of adjacent fertile lemma; chartaceous; without keels; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 7–9.5 mm long; chartaceous; without keel; 5 -veined. Lemma surface scabrous; rough generally; glabrous, or puberulous; hairy at base. Lemma apex acute; muticous. Palea 1 length of lemma; 2 -veined. Palea keels ciliolate. Palea surface scabrous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; ciliate. Anthers 3; 3–4.5 mm long. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp. Hilum linear; 0.5 length of caryopsis.

DISTRIBUTION South America: southern South America.

NOTES Poeae. Fl Pat 1995.

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