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.

Poa physoclina

HABIT Perennial; caespitose. Butt sheaths glabrous. Basal innovations intravaginal. Culms erect, or prostrate (blown flat by wind); slender; 15–40 cm long. Culm-internodes terete, or elliptical in section; distally pubescent. Leaves mostly basal. Leaf-sheaths glabrous on surface, or puberulous. Ligule an eciliate membrane; 0.3 mm long; pubescent on abaxial surface; truncate. Leaf-blades filiform; conduplicate; 10–20(–25) cm long; 0.2–0.4 mm wide; dark green. Leaf-blade surface smooth, or scaberulous; rough adaxially; puberulous; densely hairy; hairy abaxially. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; effuse; 5–12 cm long; 5–10 cm wide. Primary panicle branches spreading. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2(–4) fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 3.5–5(–6.5) mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus woolly. Floret callus hairs 1–1.5 mm long.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume oblong; 2.2–3.1 mm long; 0.9 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume primary vein scaberulous. Lower glume surface asperulous. Lower glume apex acute. Upper glume oblong; 2.5–3.5 mm long; 0.75 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scaberulous. Upper glume surface asperulous. Upper glume apex acute.

FLORETS Fertile lemma ovate; elliptic in profile; 3–4.1 mm long; membranous; keeled; 5 -veined. Lemma midvein scaberulous (above); pubescent; hairy below. Lemma surface pubescent; hairy on veins. Lemma apex acute. Palea 0.9 length of lemma. Palea keels ciliate; adorned above. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3; 1.5–2 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Australasia: Australia.

NOTES Poeae. Walsh 2009.

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