Cenchrus echinatus

HABIT Annual. Culms geniculately ascending; 15–90 cm long. Ligule a fringe of hairs. Leaf-blades 4–25 cm long; 3–10 mm wide.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; interrupted (or lax); 2–10 cm long. Primary panicle branches accrescent to a central axis; with sessile scars on axis. Panicle axis angular; bearing deciduous spikelet clusters.

Spikelets subtended by an involucre. Fertile spikelets sessile; 2–3 in the cluster. Involucre composed of bristles; connate into a cup below; with 2–5 mm connate; globose; 5–10 mm long; base obconical. Involucral bristles deciduous with the fertile spikelets; with an outer whorl of thinner bristles; inner bristles longer than outer; with longest bristle scarcely emergent; 2–5 mm long; flattened; rigid; retrorsely scaberulous; pubescent; spinose.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; acuminate; 5–7 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 1.3–3.4 mm long; 0.33–0.5 length of spikelet; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex obtuse, or acute. Upper glume ovate; 3.8–5.7 mm long; 0.75 length of spikelet; membranous; without keels; 3–5 -veined. Upper glume surface puberulous. Upper glume apex obtuse, or acute.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret ovate; 1 length of spikelet; membranous; 5 -veined; obtuse, or acute. Fertile lemma ovate; 5–7 mm long; coriaceous; much thinner on margins; without keel; 5 -veined. Lemma margins flat. Lemma apex obtuse. Palea coriaceous.

FRUIT Caryopsis with adherent pericarp; ellipsoid; dorsally compressed; 3 mm long; truncate.

DISTRIBUTION Africa: north, Macaronesia, west tropical, west-central tropical, east tropical, and western Indian ocean. Asia-temperate: western Asia, Arabia, China, and eastern Asia. Asia-tropical: India, Indo-China, Malesia, and Papuasia. Australasia: Australia. Pacific: southwestern, south-central, northwestern, and north-central. North America: southwest USA, south-central USA, southeast USA, and Mexico. South America: Mesoamericana, Caribbean, northern South America, western South America, Brazil, and southern South America.

NOTES Paniceae. FTEA.

ADDITIONAL CHARACTERS Involucre base 2.2–3.6mm wide.

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