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.

Poa papuana

HABIT Perennial; caespitose. Butt sheaths persistent and investing base of culm; with fibrous dead sheaths. Basal innovations intravaginal. Culms erect; 7–28 cm long; 2–5 -noded. Leaf-sheaths smooth; glabrous on surface. Ligule an eciliate membrane; 1–2.6 mm long; erose; obtuse, or acute. Leaf-blades erect; involute; 1.3–7 cm long; 0.25–0.5 mm wide; mid-green, or dark green. Leaf-blade venation with 5–7 secondary veins. Leaf-blade surface grooved on either side of midline; scabrous; rough adaxially; glabrous. Leaf-blade apex abruptly acute.

INFLORESCENCE Inflorescence a panicle. Peduncle 3–18 cm long; antrorsely scabrous above.

Panicle open; oblong; dense; 0.5–3.5 cm long; 0.2–1.2 cm wide. Primary panicle branches appressed, or ascending; 1–2 -nate; 0.3–1.3 cm long; bearing 1–12 fertile spikelets on each lower branch. Panicle branches stiff; terete; scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels 1.4–2.1 mm long.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets ovate; laterally compressed; 2.1–3.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus woolly.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume ovate; 1.2–2 mm long; 1 length of upper glume; membranous; 1-keeled; 1–3 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent, or distinct. Lower glume margins ciliolate. Lower glume apex acute. Upper glume ovate; 1.3–2 mm long; 0.75 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume primary vein scabrous. Upper glume margins ciliolate. Upper glume apex obtuse.

FLORETS Fertile lemma ovate; elliptic in profile; 1.9–2.5 mm long; membranous; keeled; 3–5 -veined. Lemma midvein scabrous. Lemma lateral veins obscure. Lemma surface glabrous. Lemma apex acute. Palea lanceolate; 2.6–2.8 mm long. Palea keels smooth. Rhachilla extension 0.2–0.9 mm long.

FLOWER Lodicules 2; membranous. Anthers 3; 0.75–1 mm long; pallid, or purple.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 1.4–1.6 mm long. Hilum punctiform.

DISTRIBUTION Asia-tropical: Papuasia.

NOTES Poeae. Alp Fl N Guin 1994.

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