Poa rigidula

HABIT Perennial; caespitose; clumped loosely. Basal innovations extravaginal and intravaginal. Culms erect, or geniculately ascending; 12–50 cm long. Lateral branches lacking. Leaves mostly basal. Ligule an eciliate membrane; 3.5–7 mm long; 1.25–4 mm long on basal shoots; glabrous on abaxial surface; acute. Leaf-blades erect; flat, or conduplicate; 2–12 cm long; 0.5–2 mm wide; stiff. Leaf-blade surface smooth. Leaf-blade apex acute.

INFLORESCENCE Inflorescence a panicle.

Panicle open, or contracted; lanceolate, or ovate; 3.5–8.5 cm long; 2–4.7 cm wide. Primary panicle branches ascending, or spreading, or reflexed; 2–3 -nate; 1.5–3.3 cm long; bearing 5–16 fertile spikelets on each lower branch. Panicle branches smooth.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets oblong; laterally compressed; 3.1–3.75 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus glabrous.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 1–1.5 mm long; 0.75 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface smooth. Lower glume apex acute. Upper glume ovate; 1.4–2 mm long; 0.5–0.66 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume surface smooth. Upper glume apex acute.

FLORETS Fertile lemma ovate; elliptic in profile; 2.6–3.5 mm long; membranous; keeled; 3 -veined. Lemma midvein scaberulous. Lemma surface glabrous. Lemma apex acute. Palea keels scaberulous; adorned above. Palea apex dentate; 2 -fid. Rhachilla extension 1–1.75 mm long.

FLOWER Lodicules 2; membranous. Anthers 3; 0.6–1.6 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Asia-tropical: Papuasia.

NOTES Poeae. Veldkamp 1995.

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