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 tibestica

HABIT Perennial; caespitose; clumped densely. Butt sheaths persistent and investing base of culm; with compacted dead sheaths. Culms 30–60 cm long; 3–5 -noded. Leaf-sheaths 3–12 cm long. Ligule an eciliate membrane; 5–6 mm long. Leaf-blades flat; 5–7.5 cm long; 2.5–3 mm wide. Leaf-blade surface scaberulous; glabrous. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear. Panicle axis pubescent. Panicle branches pubescent.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 0.6–0.8 mm long; pubescent; tip widened.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets elliptic; laterally compressed; 2.5–3 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma; gaping. Lower glume lanceolate; 2.4–2.6 mm long; 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 margins ciliolate. Lower glume apex acute. Upper glume lanceolate; 2.4–2.6 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume surface asperulous. Upper glume margins ciliolate. Upper glume apex acute.

FLORETS Fertile lemma oblong; 2.5 mm long; cartilaginous; without keel; 5 -veined. Lemma lateral veins obscure; excurrent. Lemma surface scaberulous; rough above; glabrous. Lemma apex dentate; 4 -fid; truncate; awned; 1 -awned. Principal lemma awn dorsal; arising 0.75 way up back of lemma; geniculate; 1.5 mm long overall; with a straight or slightly twisted column. Palea 0.8–1.1 mm long; 0.5 length of lemma; hyaline; 2 -veined.

FLOWER Lodicules 2; 0.5–0.6 mm long; membranous. Anthers 3; yellow.

DISTRIBUTION Africa: northeast tropical.

NOTES Aveneae. Mire 2005.

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