GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Deyeuxia velutina

HABIT Perennial; caespitose; clumped densely. Culms 10–30 cm long. Leaf-sheaths 3.5–5 cm long; smooth; glabrous on surface. Ligule an eciliate membrane; 2 mm long; pubescent on abaxial surface; acute. Leaf-blades curved; filiform; conduplicate; 4–8 cm long; 1 mm wide; stiff. Leaf-blade surface glabrous. Leaf-blade apex pungent.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear, or lanceolate; 1.5–5 cm long; 0.7–1 cm wide.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels bearing a few hairs, or glabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 4–4.6 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pilose. Floret callus hairs 0.33 length of lemma.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of upper glume; membranous; yellow; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume surface asperulous. Lower glume apex acute. Upper glume lanceolate; 1.3 length of adjacent fertile lemma; membranous; yellow; 1-keeled; 3 -veined. Upper glume primary vein scabrous. Upper glume surface asperulous. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 3–3.6 mm long; membranous; without keel. Lemma surface scabrous; rough above and on veins. Lemma apex erose; truncate; awned; 1 -awned. Principal lemma awn dorsal; arising 0.25–0.33 way up back of lemma; geniculate; 5–7 mm long overall; clearly exserted from spikelet; with twisted column. Palea 1 length of lemma. Rhachilla extension 1.1–1.5 mm long; pilose.

FLOWER Lodicules 2. Anthers 3; 2 mm long; purple. Stigmas 2.

FRUIT Caryopsis with adherent pericarp; fusiform; 2.5 mm long. Hilum punctiform. Disseminule comprising a floret.

DISTRIBUTION South America: southern South America.

NOTES Aveneae. Fl Pat 1995.

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