Festuca tancitaroensis

HABIT Perennial; caespitose; clumped densely. Butt sheaths persistent and investing base of culm; with fibrous dead sheaths. Basal innovations intravaginal. Culms erect; 85–130 cm long; 1–2 -noded. Leaf-sheaths glabrous on surface. Leaf-sheath auricles absent. Ligule an eciliate membrane; 1.5–2.8 mm long; truncate, or obtuse. Leaf-blades flat, or involute; 30–60 cm long; 3.3–6.5 mm wide. Leaf-blade surface ribbed; grooved adaxially; scabrous; rough abaxially. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle. Peduncle glabrous.

Panicle open; ovate; 15–21 cm long. Primary panicle branches 2 -nate. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 5–8 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 15–21 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 4.5–9 mm long; 0.66 length of upper glume; chartaceous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume surface scabrous. Lower glume apex acute. Upper glume lanceolate; 6.5–10.5 mm long; 0.75 length of adjacent fertile lemma; chartaceous; without keels; 3 -veined. Upper glume surface scabrous. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 8.7–12.5 mm long; chartaceous; without keel; 5 -veined. Lemma surface scabrous. Lemma apex acute; awned. Palea 2 -veined. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2. Anthers 3; 4–5.3 mm long. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; 5–7.5 mm long. Hilum linear.

DISTRIBUTION North America: Mexico.

NOTES Poeae. Gonz.-Ledesma 2004.

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