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 macrostachyum

HABIT Perennial; caespitose. Rhizomes short. Culms erect, or geniculately ascending; 40–100 cm long; 2–3 -noded. Ligule an eciliate membrane; 1–2 mm long; obtuse. Leaf-blades 10–16 cm long; 3–6 mm wide. Leaf-blade surface scaberulous; rough on both sides; glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong; dense, or loose; nodding. Primary panicle branches simple.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 3–6 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 20–30 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 2 mm long; glabrous. Floret callus elongated; pilose.

GLUMES Glumes persistent; similar; reaching apex of florets, or shorter than spikelet; thinner than fertile lemma. Lower glume elliptic; 10–12 mm long; 0.5–0.6 length of upper glume; membranous; without keels; 3 -veined. Lower glume apex setaceously attenuate. Upper glume lanceolate; 18–25 mm long; 1.3–1.4 length of adjacent fertile lemma; membranous; without keels; 7 -veined. Upper glume apex setaceously attenuate.

FLORETS Fertile lemma elliptic; 14–18 mm long; coriaceous; without keel; 7 -veined. Lemma apex dentate; 2 -fid; setaceously attenuate; awned; 1 -awned. Principal lemma awn dorsal; arising 0.66 way up back of lemma; geniculate; 20–30 mm long overall; with twisted column. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 8–9 mm long. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp; hairy at apex. Hilum linear.

DISTRIBUTION Africa: north.

NOTES Aveneae. Fl Afr N.

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