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 imbecilla

HABIT Perennial; caespitose; clumped loosely. Rhizomes short. Basal innovations extravaginal. Culms 15–50 cm long. Culm-nodes swollen. Lateral branches lacking. Leaf-sheaths smooth; glabrous on surface. Ligule an eciliate membrane; 0.2–0.4 mm long; scaberulous on abaxial surface; entire; truncate. Leaf-blades filiform; conduplicate; 5–12 cm long; 0.5–1 mm wide. Leaf-blade surface smooth; glabrous. Leaf-blade margins scaberulous. Leaf-blade apex acute.

INFLORESCENCE Inflorescence a panicle. Peduncle smooth.

Panicle open; ovate; 8–15 cm long. Primary panicle branches spreading. Panicle axis smooth, or scaberulous. Panicle branches capillary; scaberulous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; scabrous.

FERTILE SPIKELETS Spikelets comprising 3–4 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 3–4 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes 0.5–1 mm long; smooth. Floret callus glabrous.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 0.8–1.5 mm long; 0.7–0.8 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex obtuse. Upper glume lanceolate; 1.3–1.8 mm long; 0.7–0.8 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume margins scaberulous. Upper glume apex obtuse.

FLORETS Fertile lemma elliptic; elliptic in profile; 1.8–2.2 mm long; membranous; keeled; 5 -veined. Lemma lateral veins with distinct primaries but obscure intermediates. Lemma surface scaberulous; rough above and on veins; glabrous. Lemma margins scaberulous. Lemma apex obtuse. Palea 1.2–2 mm long. Palea keels ciliate; adorned above. Palea surface scabrous.

FLOWER Lodicules 2; 0.2 mm long; membranous. Anthers 3; 0.2–0.4 mm long.

FRUIT Caryopsis with adherent pericarp; 1 mm long. Hilum punctiform.

DISTRIBUTION Australasia: New Zealand.

NOTES Poeae. Edgar 1995.

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