Deyeuxia alba

HABIT Perennial. Rhizomes elongated. Culms erect; 40–80 cm long. Ligule an eciliate membrane; 0.5–1 mm long; truncate. Leaf-blades 4–15 cm long; 3–6 mm wide. Leaf-blade surface scabrous; rough on both sides. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear; interrupted; dense; 14–25 cm long; 2–3 cm wide. Primary panicle branches appressed; bearing spikelets almost to the base.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels pubescent.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 7.5–10 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus bearded. Floret callus hairs 1.2 length of lemma.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex attenuate. Upper glume lanceolate; 7.5–10 mm long; 1.7–1.8 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scabrous. Upper glume apex attenuate.

FLORETS Fertile lemma lanceolate; 4.5–5.5 mm long; membranous; without keel; 5 -veined. Lemma lateral veins obscure. Lemma surface scaberulous. Lemma apex obtuse, or acute; awned; 1 -awned. Principal lemma awn dorsal; arising 0.75–0.85 way up back of lemma; straight; spreading; 4.5–6 mm long overall. Rhachilla extension 1.8–2.1 mm long; pilose; hairy above.

FLOWER Lodicules 2. Anthers 3. Stigmas 2.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform. Disseminule comprising a floret.

DISTRIBUTION South America: western South America, Brazil, and southern South America.

NOTES Aveneae. Tovar 1995.

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