Muhlenbergia xanthodas

HABIT Perennial; caespitose; clumped densely. Culms erect; 60–100 cm long. Culm-internodes distally glabrous. Leaf-sheaths keeled; scaberulous; glabrous on surface. Leaf-sheath auricles absent. Ligule an eciliate membrane; 6–10 mm long. Leaf-blades conduplicate; 30–40 cm long; 2–3 mm wide. Leaf-blade surface scabrous. Leaf-blade margins scabrous. Leaf-blade apex attenuate; filiform.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear; 20–40 cm long; 2–3 cm wide. Primary panicle branches appressed; 4.5–6 cm long; bearing spikelets almost to the base.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels scaberulous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 2–3 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent.

GLUMES Glumes persistent; similar; reaching apex of florets; shiny. Lower glume lanceolate; 2–3 mm long; 1 length of upper glume; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 2–3 mm long; 1 length of adjacent fertile lemma; membranous; without keels; 1 -veined. Upper glume lateral veins absent. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 2–2.8 mm long; membranous; without keel; 3 -veined. Lemma midvein pubescent; hairy at base. Lemma apex acute; awned; 1 -awned. Principal lemma awn 7–20 mm long overall. Palea 2 -veined. Palea surface glabrous.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 1.5–1.8 mm long.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION North America: Mexico.

NOTES Eragrostideae. Fl Meso-Am 1995.

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