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 neglecta

HABIT Perennial; caespitose. Rhizomes elongated. Culms erect; 30–100 cm long; 2–3 -noded. Leaf-sheaths without keel; smooth; glabrous on surface. Ligule an eciliate membrane; 1–3 mm long; entire; truncate. Leaf-blades flat, or involute; 30–60 cm long; 1.5–5 mm wide; stiff. Leaf-blade surface ribbed; pubescent; hairy adaxially. Leaf-blade margins scaberulous. Leaf-blade apex attenuate; filiform.

INFLORESCENCE Inflorescence a panicle. Peduncle smooth, or antrorsely scabrous above.

Panicle contracted; lanceolate to oblong; 7–20 cm long; 1–3 cm wide. Primary panicle branches appressed; 3–6 cm long. Panicle branches terete; scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; terete; 0.5–2 mm long; scabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 3–4 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus bearded. Floret callus hairs 0.6–0.75 length of lemma.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma; gaping. Lower glume elliptic; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume surface asperulous. Lower glume apex acute. Upper glume elliptic; 1.2–1.3 length of adjacent fertile lemma; membranous; 1-keeled; 1–3 -veined. Upper glume primary vein scabrous. Upper glume surface asperulous. Upper glume apex acute.

FLORETS Fertile lemma oblong; 2.5–3.5 mm long; membranous; without keel; 5 -veined. Lemma surface asperulous. Lemma apex dentate; 4 -fid; truncate; awned; 1 -awned. Principal lemma awn dorsal; arising 0.3–0.5 way up back of lemma; straight; 1–2 mm long overall; not or scarcely exserted from spikelet. Palea elliptic; 0.6–0.7 length of lemma; hyaline; 2 -veined. Rhachilla extension 0.2 length of fertile floret; pilose.

FLOWER Lodicules 2; lanceolate. Anthers 3; 2–2.5 mm long. Stigmas 2.

FRUIT Caryopsis with adherent pericarp; fusiform. Hilum punctiform. Endosperm farinose. Disseminule comprising a floret.

DISTRIBUTION Europe: northern, central, southeastern, and eastern. Asia-temperate: Siberia, Soviet far east, Soviet Middle Asia, Caucasus, China, Mongolia, and eastern Asia. North America: Subarctic, western Canada, eastern Canada, northwest USA, north-central USA, northeast USA, southwest USA, south-central USA, and southeast USA. South America: western South America and southern South America.

NOTES Aveneae. CEH.

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