Helictotrichon whitei

HABIT Perennial; caespitose. Butt sheaths persistent and investing base of culm; with fibrous dead sheaths. Culms erect, or geniculately ascending; 20–35 cm long; 3 -noded. Lateral branches lacking. Leaves mostly basal. Leaf-sheaths scaberulous. Ligule an eciliate membrane; 5–8 mm long. Leaf-blades 7–15 cm long; 1–1.8 mm wide. Leaf-blade surface glabrous. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; lanceolate; 5–10 cm long; 1–1.5 cm wide. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 4–5 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 7–10 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes pilose; hairy above. Floret callus pubescent.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 2–2.3 mm long; 0.7–0.8 length of upper glume; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 2.5–3 mm long; 0.6–0.7 length of adjacent fertile lemma; membranous; without keels; 3 -veined. Upper glume apex acute.

FLORETS Fertile lemma ovate; 4–4.5 mm long; chartaceous; without keel; 7 -veined. Lemma surface papillose and tuberculate. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.5 way up back of lemma; geniculate; 8–12 mm long overall; with twisted column. Palea keels winged; narrowly winged; ciliolate; adorned above. Rhachilla extension 0.75 length of fertile floret. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 1–3; 0.3–0.5 mm long. Ovary pubescent on apex.

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

DISTRIBUTION Australasia: Australia.

NOTES Aveneae. Tothill 1993.

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