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 elongatum

HABIT Perennial; caespitose. Butt sheaths dark brown. Culms erect, or decumbent; 45–150 cm long. Leaves mostly basal. Ligule an eciliate membrane; 2–4 mm long. Leaf-blades 15–45 cm long; 2–5 mm wide. Leaf-blade venation distinct. Leaf-blade surface glabrous, or pilose; sparsely hairy.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear, or oblong; dense, or loose; equilateral, or nodding; 10–35 cm long. Primary panicle branches appressed, or ascending. Panicle branches scaberulous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 8–14 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 2 mm long; pilose. Floret callus pilose.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma. Lower glume elliptic; 5–10 mm long; 0.7–0.9 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume apex acute. Upper glume elliptic; 7–11 mm long; 1 length of adjacent fertile lemma; membranous; with hyaline margins; 1-keeled; 3–5 -veined. Upper glume apex acute.

FLORETS Fertile lemma elliptic; 6.5–11 mm long; chartaceous, or cartilaginous; pallid, or purple; without keel; 7–9 -veined. Lemma surface smooth, or granulose, or scaberulous. Lemma apex dentate; 2 -fid; acute, or setaceously attenuate; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; geniculate; 15–20 mm long overall; with twisted column. Palea 0.6–0.8 length of lemma. Palea keels ciliolate. Rhachilla extension 0.75 length of fertile floret; pilose.

FLOWER Anthers 3; 2.5–3.5 mm long. Ovary pubescent on apex.

FRUIT Caryopsis with adherent pericarp; 3 mm long; hairy at apex. Hilum linear.

DISTRIBUTION Africa: west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, and western Indian ocean. Asia-temperate: Arabia.

NOTES Aveneae. FTEA.

ADDITIONAL CHARACTERS Rhachilla hairs shorter than itself.

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