GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Cenchrus pilosus

HABIT Annual; caespitose. Culms 30–60 cm long. Leaf-sheaths keeled; smooth, or antrorsely scabrous. Ligule a fringe of hairs; 0.5–1.6 mm long. Leaf-blades 6–30 cm long; 4–11 mm wide. Leaf-blade surface glabrous; hairless except near base.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; dense (internodes 1–2.5mm); 2–13 cm long; 0.8–2.7 cm wide. Primary panicle branches accrescent to a central axis; with sessile scars on axis. Panicle axis angular; scabrous; 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 2–4 mm connate; globose; 5–8 mm long; base obconical. Involucral bristles deciduous with the fertile spikelets; numerous; with an outer whorl of thinner bristles; inner bristles longer than outer; 3–6 mm long; flattened; flexible; smooth; pubescent; attenuate.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; acuminate; 6–7 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 1–4 mm long; 0.2–0.5 length of spikelet; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 3–6 mm long; 0.5–0.8 length of spikelet; membranous; without keels; 3–5 -veined. Upper glume apex acute.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret ovate; 4–7 mm long; 0.6–1 length of spikelet; membranous; 3–7 -veined; acute. Fertile lemma ovate; 5–7.5 mm long; coriaceous; much thinner on margins; without keel; 3 -veined. Lemma margins flat. Lemma apex obtuse. Palea coriaceous.

FLOWER Anthers 0.9–1.8 mm long.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION North America: Mexico. South America: Mesoamericana, Caribbean, northern South America, and western South America.

NOTES Paniceae. De Lisle.

ADDITIONAL CHARACTERS Outer bristles at least twice length of body.

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