|
Note - this takes you off
of our website |
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 pithogastrum
HABIT Perennial; caespitose. Butt sheaths distinctly ribbed; glabrous. Culms erect; 50–100 cm long; 1–2 mm diam.; 2–3 -noded; not swollen at the base, or swollen at the base; forming an ovoid corm. Culm-internodes terete, or elliptical in section; ridged. Culm-nodes glabrous. Leaf-sheaths ribbed; smooth. Ligule an eciliate membrane; 2–5 mm long; acute. Leaf-blades flat, or involute; 10–20 cm long; 1.5–5 mm wide. Leaf-blade surface ribbed; grooved adaxially; scaberulous; rough adaxially.
INFLORESCENCE Inflorescence a panicle.
Panicle contracted; 10–25 cm long. Primary panicle branches 2 -nate; 4–8 cm long.
Spikelets solitary. Fertile spikelets pedicelled. Pedicels 10–30 mm long; ciliate.
FERTILE SPIKELETS Spikelets comprising 2–6 fertile florets; with a barren rhachilla extension, or with diminished florets at the apex. Spikelets oblong; laterally compressed; 8–15 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; 3.6–5.3 mm long; 0.75 length of upper glume; membranous; 1-keeled; 3–5 -veined. Lower glume apex acute. Upper glume elliptic; 4.7–7.3 mm long; 0.8–1 length of adjacent fertile lemma; membranous; 1-keeled; 5–7 -veined. Upper glume apex acute.
FLORETS Fertile lemma elliptic; 5.6–7.5 mm long; cartilaginous; without keel; 7 -veined. Lemma apex dentate; 4 -fid; with outer lobes shorter; with lobes 0.3–0.65 mm long; awned; 1 -awned. Principal lemma awn dorsal; arising 0.66–0.75 way up back of lemma; geniculate; flat below; 9–16 mm long overall; with 6–11 mm long limb; with twisted column. Column of lemma awn 3–5 mm long; scabrous. Palea 0.55–0.7 length of lemma. Palea keels ciliate. Apical sterile florets resembling fertile though underdeveloped.
FLOWER Lodicules 2; 1.3–1.75 mm long; membranous; glabrous; acute. Anthers 3; 0.6–1.5 mm long; retained within floret. Ovary glabrous.
FRUIT Caryopsis with adherent pericarp; 1.6–2.1 mm long; light brown; glabrous. Embryo 0.25–0.3 length of caryopsis. Hilum linear; 0.4–0.5 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.
