GrassBase - The Online World Grass Flora


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

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

Deyeuxia yanyuanensis

HABIT Perennial. Rhizomes elongated. Culms erect; 40–60 cm long; 1 mm diam.; 2–3 -noded. Leaf-sheaths mostly shorter than adjacent culm internode; antrorsely scabrous; glabrous on surface. Ligule an eciliate membrane; 3 mm long; membranous. Leaf-blades convolute; 5–9.5 cm long; 1.5 mm wide. Leaf-blade surface scaberulous; glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; 6–11 cm long. Primary panicle branches 5–6 -nate; 2.5 cm long. Panicle branches capillary; glabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels clavate; smooth.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 3–3.7 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent. Floret callus hairs 0.5 mm long; 0.2 length of lemma.

GLUMES Glumes persistent; similar; exceeding apex of florets. Lower glume lanceolate; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface glabrous. Lower glume apex acute. Upper glume lanceolate; 3–3.7 mm long; 1.1 length of adjacent fertile lemma; membranous; 1-keeled. Upper glume surface glabrous. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 2.7–3.3 mm long; membranous; without keel; 5 -veined. Lemma apex entire; emarginate; pungent; 1 -awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; straight; 2–6.5 mm long overall. Palea 1.5–2 mm long; 2 -veined. Palea apex dentate; 4 -fid. Rhachilla extension 1.5–2.5 mm long; villous; with 2–3 mm long hairs.

FLOWER Lodicules 2. Anthers 3.

FRUIT Caryopsis with adherent pericarp; ovoid; 1.7 mm long. Hilum punctiform. Disseminule comprising a floret.

DISTRIBUTION Asia-temperate: China.

NOTES Aveneae. Yang 2003.

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