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.

Helictotrichon gervaisii

HABIT Perennial; caespitose. Culms 50–80 cm long; 1–2 mm diam. Culm-internodes antrorsely scabrous. Culm-nodes purple. Leaf-sheaths antrorsely scabrous. Ligule an eciliate membrane; 4–7 mm long; 1.5–3.5 mm long on basal shoots; acute. Leaf-blades filiform; convolute; 10–40 cm long; 0.6 mm wide; 3–8 cm long at summit of culm; grey-green. Leaf-blade venation with subepidermal sclerenchyma free from veins; without layer of subepidermal sclerenchyma masking vein striation. Leaf-blade surface ribbed; grooved abaxially.

INFLORESCENCE Inflorescence a panicle; comprising 13–21 fertile spikelets.

Panicle open; linear, or oblong; 10–22 cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 7–9 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 18–30 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1.5–2.5 mm long; glabrous. Floret callus pubescent. Floret callus hairs 0.5–1 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma. Lower glume elliptic; 10–12 mm long; 0.75–0.85 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume apex acute. Upper glume elliptic; 12–15 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma elliptic; 12–15 mm long; cartilaginous; much thinner above; without keel; 5–7 -veined. Lemma surface puberulous; hairy below. Lemma apex dentate; 2 -fid; awned; 3 -awned. Principal lemma awn dorsal; arising 0.5–0.66 way up back of lemma; geniculate; flat below; 14–24 mm long overall; with twisted column. Lateral lemma awns 1 mm long. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3. Ovary pubescent on apex.

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

DISTRIBUTION Europe: southwestern.

NOTES Aveneae. Fl Eur 1995.

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