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.

Helictotrichon recurvatum

HABIT Perennial; caespitose. Butt sheaths distinctly ribbed; glabrous, or sparsely hairy. Culms erect; 80–150 cm long; 1–1.5 mm diam.; 3–5 -noded. Culm-internodes terete, or elliptical in section; ridged; smooth, or scaberulous. Culm-nodes glabrous. Leaf-sheaths ribbed; smooth, or scaberulous. Ligule an eciliate membrane; 7–11 mm long; acute. Leaf-blades flat, or involute; 15–30 cm long; 2–3 mm wide. Leaf-blade surface ribbed; grooved adaxially and abaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; 10–30 cm long. Primary panicle branches 2–3 -nate; 3–6 cm long. Panicle axis scabrous. Panicle branches hispid.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 5–10 mm long; glabrous, or pubescent.

FERTILE SPIKELETS Spikelets comprising 4–6 fertile florets; with a barren rhachilla extension, or with diminished florets at the apex. Spikelets oblong; laterally compressed; 7–11 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma. Lower glume lanceolate; 3.3–5.5 mm long; 0.8–1 length of upper glume; membranous; much thinner above; much thinner on margins; 1-keeled; 1–3 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent, or distinct. Lower glume apex acute, or acuminate. Upper glume elliptic; 4–5.4 mm long; 1 length of adjacent fertile lemma; membranous; much thinner above; with hyaline margins; 1-keeled; 3–5 -veined. Upper glume apex acute.

FLORETS Fertile lemma elliptic; 4–5.2 mm long; cartilaginous; without keel; 5–7 -veined. Lemma surface hispid. Lemma apex dentate; 4 -fid; with simple equal lobes, or with outer lobes shorter; with lobes 0.43–1 mm long; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5–0.66 way up back of lemma; geniculate; 9–18 mm long overall; with 5–13 mm long limb; with a straight or slightly twisted column. Column of lemma awn 3.3–3.5 mm long; hirtellous. Palea 0.7–0.95 length of lemma. Palea keels eciliate, or ciliolate; adorned above. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; 0.8–1.3 mm long; membranous; glabrous, or ciliate; acute. Anthers 3; 1.2–2 mm long; eventually exserted. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; 1.8–2.3 mm long; light brown; glabrous. Embryo 0.1–0.3 length of caryopsis. Hilum linear; 0.2–0.35 length of caryopsis.

DISTRIBUTION Australasia: Australia.

NOTES Aveneae. Jacobs & Lap 1994.

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