Helictotrichon argaeum

HABIT Perennial; caespitose; clumped loosely. Culms erect, or geniculately ascending; 17–48 cm long. Culm-internodes terete. Lateral branches lacking. Leaves mostly basal. Leaf-sheaths smooth; glabrous on surface. Ligule an eciliate membrane; 1–4 mm long; acuminate. Leaf-blades conduplicate; 3–11 cm long; 1–3 mm wide; glaucous. Leaf-blade margins scaberulous. Leaf-blade apex obtuse.

INFLORESCENCE Inflorescence a panicle; comprising 5–16 fertile spikelets.

Panicle contracted; oblong; 3.5–7 cm long; 0.5–2 cm wide.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 1–8.5 mm long; smooth, or scaberulous.

FERTILE SPIKELETS Spikelets comprising 4–6 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 16–19 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 1.6–2.4 mm long; pubescent; with 0.2–0.3 mm long hairs. Floret callus pubescent. Floret callus hairs 0.3–0.6 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma; shiny. Lower glume lanceolate; 10–15 mm long; 0.75 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume apex acute. Upper glume lanceolate; 12–16 mm long; 1.2–1.3 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma oblong; 10–12 mm long; cartilaginous; light brown, or red; without keel; 5 -veined. Lemma apex dentate; 2 -fid; acute; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; geniculate; flat below; 14–15 mm long overall; with twisted column. Palea 7.5–9 mm long. Palea keels ciliolate. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 4–4.7 mm long. Ovary pubescent on apex.

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

DISTRIBUTION Asia-temperate: western Asia.

NOTES Aveneae. Fl Turk 1993.

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