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 mesathera

HABIT Perennial; caespitose. Culms erect, or geniculately ascending; 80–1120 cm long; 4–5 -noded. Culm-nodes glabrous. Leaf-sheaths striately veined; glabrous on surface. Ligule an eciliate membrane; 2–4 mm long; scaberulous on abaxial surface; entire, or erose; truncate. Leaf-blades flat, or convolute; 8–45 cm long; 2–3 mm wide. Leaf-blade surface scabrous; rough on both sides; glabrous, or hispid; hairy adaxially. Leaf-blade margins scabrous. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; linear; interrupted; 15–25 cm long; 1–2 cm wide. Primary panicle branches appressed. Panicle axis scabrous. Panicle branches scabrous.

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

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 3 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent. Floret callus hairs 0.2–1 mm long.

GLUMES Glumes persistent; similar; reaching apex of florets; firmer than fertile lemma; gaping. Lower glume lanceolate; 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 lanceolate; 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 apex acute.

FLORETS Fertile lemma lanceolate; 3 mm long; membranous; without keel; 5 -veined. Lemma surface asperulous. Lemma apex dentate; 4 -fid; truncate; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; straight; 3.5–4 mm long overall; without a column. Palea 1 length of lemma. Palea keels scaberulous; adorned above.

FLOWER Lodicules 2. Anthers 3; 1 mm long. Stigmas 2.

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

DISTRIBUTION Australasia: Australia.

NOTES Aveneae. Vickery 1994.

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