Poa orthophylla

HABIT Perennial. Basal innovations extravaginal. Culms erect; 15–30 cm long. Culm-internodes terete. Leaves mostly basal. Leaf-sheaths striately veined; glabrous on surface. Ligule an eciliate membrane; acute. Leaf-blades flat; 3–6 cm long; 4–5 mm wide. Leaf-blade surface scabrous; glabrous. Leaf-blade apex obtuse; apiculate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; ovate; effuse; 4–7 cm long; with spikelets clustered towards branch tips. Primary panicle branches 1–2 -nate. Panicle axis scabrous. Panicle branches flexuous; scabrous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2 fertile florets; with a barren rhachilla extension. Spikelets oblong, or ovate; laterally compressed; 5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus woolly.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 4 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface scabrous. Lower glume apex acute. Upper glume lanceolate; 4 mm long; 1 length of adjacent fertile lemma; membranous; 1-keeled; 3 -veined. Upper glume surface scabrous. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 3.5–4 mm long; membranous; keeled; 3–5 -veined. Lemma midvein scabrous. Lemma lateral veins with distinct primaries but obscure intermediates, or distinct. Lemma surface asperulous. Lemma apex acute. Palea 1 length of lemma. Palea keels scabrous. Palea apex dentate; 2 -fid.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION South America: western South America.

NOTES Poeae. Pilger 2010.

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