Pennisetum annuum

HABIT Annual. Culms slender; 30–70 cm long. Culm-nodes glabrous. Ligule a fringe of hairs. Leaf-blades lanceolate; 6–20 cm long; 5–10 mm wide. Leaf-blade surface scabrous.

INFLORESCENCE Inflorescence a panicle; terminal and axillary.

Panicle spiciform; elliptic; 2.5–3 cm long. Primary panicle branches accrescent to a central axis; with sessile scars on axis. Panicle axis with rounded ribs; glabrous; bearing deciduous spikelet clusters.

Spikelets subtended by an involucre. Fertile spikelets sessile; 1(–2) in the cluster. Involucre composed of bristles; 2.5 mm long; base truncate. Involucral bristles deciduous with the fertile spikelets; numerous; with one conspicuously longer bristle; 11–12 mm long; terete; flexible; antrorsely scaberulous; glabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 5 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.25 length of spikelet; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 1 length of spikelet; membranous; without keels; 7 -veined. Upper glume apex acute.

FLORETS Basal sterile florets male, or barren; with palea. Lemma of lower sterile floret oblong; 1 length of spikelet; membranous; 5 -veined; acute. Fertile lemma lanceolate; 5 mm long; coriaceous; without keel. Lemma margins flat. Lemma apex acute. Palea 1 length of lemma; coriaceous.

FLOWER Lodicules absent. Anthers 3.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: western South America.

NOTES Paniceae. Turpe 1994.

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