Muhlenbergia aurea

HABIT Perennial; caespitose; clumped densely. Culms erect; 75–100 cm long. Culm-internodes distally glabrous. Leaf-sheaths keeled; antrorsely scabrous. Leaf-sheath auricles erect; 0.8–3 mm long. Ligule an eciliate membrane; 0.5–1.5 mm long. Leaf-blades flat; 20–45 cm long; 2.5–5 mm wide. Leaf-blade surface scaberulous; rough on both sides. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; lanceolate; dense; 25–35 cm long; 7–8 cm wide. Primary panicle branches 12–15 cm long. Panicle branches flexible.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; flexuous; 2–4 mm long; scaberulous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 1.7–2.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent. Floret callus hairs 0.5 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 1.5–2 mm long; 1 length of upper glume; membranous; yellow; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume lanceolate; 1.5–2 mm long; 0.9 length of adjacent fertile lemma; membranous; yellow; without keels; 1 -veined. Upper glume lateral veins absent. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; 1.7–2.5 mm long; membranous; without keel; 3 -veined. Lemma midvein pubescent; hairy below. Lemma surface scabrous; rough above. Lemma margins pubescent; hairy below. Lemma apex acute; awned; 1 -awned. Principal lemma awn 10–15 mm long overall. Palea 2 -veined. Palea surface smooth, or scaberulous.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 1 mm long. Filaments free.

FRUIT Caryopsis with adherent pericarp; fusiform; 1 mm long.

DISTRIBUTION South America: Mesoamericana.

NOTES Eragrostideae. Fl Meso-Am 1995.

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