Phalaris platensis

HABIT Annual; caespitose. Culms 20–40 cm long. Ligule an eciliate membrane. Leaf-blades 5–10 cm long; 3–5 mm wide.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; continuous, or interrupted; 3–8 cm long.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 2 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets obovate; laterally compressed; compressed strongly; 3.9–5.1 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume elliptic; 3.9–5.1 mm long; 1 length of upper glume; chartaceous; 1-keeled; wingless, or winged on keel; winged narrowly; winged above; 3–5 -veined. Lower glume primary vein scabrous. Lower glume surface scabrous; rough on veins. Lower glume apex acute. Upper glume elliptic; 3.9–5.1 mm long; 1.3–1.5 length of adjacent fertile lemma; chartaceous; 1-keeled; wingless, or winged on keel; winged near apex; 3 -veined. Upper glume primary vein scabrous. Upper glume surface scabrous; rough on veins. Upper glume apex acute.

FLORETS Basal sterile florets similar; barren; without significant palea; attached to and deciduous with the fertile. Lemma of lower sterile floret linear; 0.8–1.8 mm long; 0.3–0.4 length of fertile lemma; glabrous. Fertile lemma elliptic; laterally compressed; 2.7–3.6 mm long; cartilaginous; shiny; keeled; 5 -veined. Lemma surface pubescent; hairy below. Lemma apex acuminate. Palea cartilaginous; 2 -veined; without keels. Palea surface pubescent; hairy on back.

FLOWER Lodicules 2; membranous. Anthers 3. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; 1.7–1.9 mm long. Hilum linear.

DISTRIBUTION South America: Brazil and southern South America.

NOTES Aveneae. Anderson.

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