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 deschampsiiformis

HABIT Perennial; caespitose; clumped densely. Butt sheaths coriaceous; persistent and investing base of culm. Basal innovations intravaginal. Culms erect; 35–50 cm long; 2 -noded. Culm-internodes smooth; distally glabrous. Lateral branches lacking. Leaf-sheaths smooth; glabrous on surface. Ligule an eciliate membrane; 3–7 mm long; obtuse. Leaf-blades erect; filiform; involute; 8–19 cm long; 1–1.2 mm wide; stiff. Leaf-blade surface ribbed; grooved adaxially; smooth; glabrous. Leaf-blade apex obtuse.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong; 13 cm long; 2–3 cm wide; contracted about primary branches. Primary panicle branches 4–9 cm long. Panicle axis scabrous. Panicle branches terete; scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; terete; 1–4 mm long.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension, or with diminished florets at the apex. Spikelets oblong; laterally compressed; 8–10 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus bearded. Floret callus hairs 1–1.6 mm long.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma; gaping. Lower glume linear, or lanceolate; 7–9 mm long; 0.9 length of upper glume; chartaceous; 1-keeled; 1 -veined. Lower glume primary vein smooth, or scaberulous. Lower glume lateral veins absent. Lower glume apex acute. Upper glume oblong; 8–10 mm long; chartaceous; 1-keeled; 2–3 -veined. Upper glume primary vein smooth. Upper glume apex acute.

FLORETS Fertile lemma oblong; 4.5–5 mm long; chartaceous; without keel; 7 -veined. Lemma apex dentate; 2 -fid; with lateral lobes bidentate; awned; 1 -awned. Principal lemma awn dorsal; arising 0.33 way up back of lemma; flexuous, or geniculate; 5.5–8 mm long overall; without a column, or with a straight or slightly twisted column. Palea oblong; 1 length of lemma; hyaline; 2 -veined. Palea keels scaberulous. Rhachilla extension 2–3 mm long; villous. Apical sterile florets 0–1 in number; rudimentary. Apical sterile lemmas awned; 1 -awned. Apical sterile lemma awns 0–3 mm long.

FLOWER Lodicules 2; membranous. Anthers 3. Stigmas 2.

FRUIT Caryopsis with adherent pericarp; oblong; 2 mm long; dark brown. Hilum elliptic.

DISTRIBUTION Antarctic: Subantarctic islands.

NOTES Aveneae. CEH 1999.

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