Helictotrichon leianthum

HABIT Perennial; caespitose. Culms erect; 60 cm long; 2 mm diam.; 2–3 -noded. Culm-internodes distally glabrous, or pubescent. Culm-nodes constricted. Leaf-sheaths loose; longer than adjacent culm internode; glabrous on surface, or puberulous. Leaf-sheath oral hairs pubescent. Ligule an eciliate membrane; 1 mm long; truncate. Leaf-blades flat, or convolute; 10–20 cm long; 3–6 mm wide. Leaf-blade surface pubescent; hairy adaxially.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear, or oblong; nodding; 15–18 cm long. Primary panicle branches spreading; 2 -nate; bearing 1–4 fertile spikelets on each lower branch.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 10 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 2 mm long; pilose; with 1.2 mm long hairs. Floret callus pilose. Floret callus hairs 1 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma. Lower glume elliptic; 5 mm long; 0.75 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume elliptic; 7 mm long; 0.75 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 9–10 mm long; cartilaginous; without keel; 5–7 -veined. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.4 way up back of lemma; geniculate; 18–20 mm long overall; with twisted column. Apical sterile florets resembling fertile though underdeveloped.

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

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

DISTRIBUTION Asia-temperate: China.

NOTES Aveneae. Keng 1995.

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