Polypogon exasperatus

HABIT Perennial; caespitose. Rhizomes absent, or elongated. Culms erect, or geniculately ascending; (7–)20–50 cm long. Leaf-sheaths smooth. Ligule an eciliate membrane; 0.5–1.5 mm long; truncate, or obtuse. Leaf-blades 5–15 cm long; 2–5 mm wide. Leaf-blade surface smooth, or scabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle contracted; lanceolate, or elliptic; 7–25 cm long. Primary panicle branches whorled at most nodes; bearing spikelets almost to the base. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform; 2–4 mm long; scabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets cuneate; laterally compressed; 2.8–3.5 mm long; falling entire; deciduous with the pedicel. Spikelet callus pubescent. Floret callus glabrous.

GLUMES Glumes similar; exceeding apex of florets; firmer than fertile lemma; gaping. Lower glume lanceolate; 2.8–3.5 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; muticous. Upper glume lanceolate; 2.8–3.5 mm long; 2–3 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume surface scabrous. Upper glume apex acute; muticous.

FLORETS Fertile lemma ovate; 1.1–1.5 mm long; membranous; without keel; 5 -veined. Lemma apex dentate; 4 -fid; truncate; awned; 1 -awned. Principal lemma awn subapical; 1.2–3.5 mm long overall. Palea 0.4–0.7 length of lemma; hyaline.

FLOWER Lodicules 2; membranous. Anthers 3; 0.7–0.9 mm long.

FRUIT Caryopsis with adherent pericarp; oblong.

DISTRIBUTION South America: northern South America, western South America, Brazil, and southern South America.

NOTES Aveneae. Fl Pat.

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