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 tarmensis

HABIT Perennial; caespitose. Basal innovations extravaginal and intravaginal. Culms 50–90 cm long. Leaf-sheaths scaberulous; glabrous on surface. Ligule an eciliate membrane; 1–3 mm long. Leaf-blades filiform; involute; 10–40 cm long; 0.4–0.7 mm wide. Leaf-blade surface smooth, or scaberulous.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear; interrupted; 10–20 cm long. Primary panicle branches appressed; 7–9 cm long. Panicle axis scaberulous. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels pubescent.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 6–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent. Floret callus hairs 0.5–0.8 mm long.

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 smooth, or scaberulous. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume lanceolate; 6–7 mm long; 1.3–1.4 length of adjacent fertile lemma; membranous; 1-keeled. Upper glume primary vein smooth, or scaberulous. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; 4.5–5 mm long; membranous; without keel. Lemma surface scaberulous. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.33 way up back of lemma; geniculate; 6.5–7.5 mm long overall; with twisted column. Palea 4.75 mm long. Rhachilla extension 1.5–3 mm long; 0.66 length of fertile floret; pubescent; with 1.5–2 mm long hairs.

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

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

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

NOTES Aveneae. Tovar 1995.

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