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 expansa

HABIT Perennial. Culms geniculately ascending; 50–60 cm long. Lateral branches lacking. Leaf-sheaths retrorsely scabrous; glabrous on surface. Ligule an eciliate membrane; 1–2 mm long. Leaf-blades flat, or involute; 15–20 cm long; 5–10 mm wide; 2–4 cm long at summit of culm. Leaf-blade surface scabrous; rough adaxially. Leaf-blade apex hardened.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; oblong; 8–15 cm long. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 7 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus bearded. Floret callus hairs 4–5 mm long; 0.5–0.6 length of lemma.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 7 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume lanceolate; 7 mm long; 2 length of adjacent fertile lemma; membranous; 1-keeled. Upper glume primary vein scabrous. Upper glume apex acuminate.

FLORETS Fertile lemma oblong; 3–4 mm long; membranous; without keel; 5 -veined. Lemma apex dentate; 4 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; curved; 5 mm long overall. Palea 2.5–3 mm long; hyaline; 2 -veined. Palea keels scaberulous. Rhachilla extension 0.5–2 mm long; pilose.

FLOWER Lodicules 2. Anthers 3. Stigmas 2.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Pacific: north-central.

NOTES Aveneae. Hitchcock 1993.

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