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.

Ctenium canescens

HABIT Perennial. Rhizomes short; scaly. Glands wart-like. Culms 90–120 cm long. Ligule an eciliate membrane; erose. Leaf-blades 15–30 cm long; 1–5 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2–5; digitate; straight, or arcuate; unilateral; 7–17 cm long. Rhachis semiterete; glabrous on surface; ciliate on margins; terminating in a barren extension; extension subulate. Spikelet packing broadside to rhachis; crowded; regular; 2 -rowed.

Spikelets pectinate; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 2 basal sterile florets; 1 fertile florets; with diminished florets at the apex. Spikelets cuneate; laterally compressed; 7–9 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pilose.

GLUMES Glumes persistent; dissimilar; exceeding apex of florets; gaping. Lower glume lanceolate; 0.25–0.33 length of upper glume; hyaline; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume lanceolate; 7–9 mm long; 1.7–1.8 length of adjacent fertile lemma; membranous; glandular (on keel); 1-keeled; 2 -veined. Upper glume primary vein tuberculate; ciliate. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn dorsal and oblique; 3–5 mm long.

FLORETS Basal sterile florets dissimilar; barren; without significant palea; attached to and deciduous with the fertile. Lemma of lower sterile floret oblong; 0.66 length of fertile lemma; membranous; 1-keeled; 3 -veined; ciliate on margins; cuspidate; awned. Awn of lower sterile floret dorsal; 6 mm long. Lemma of upper sterile floret oblong; 1.1 length of lower sterile floret; membranous; eciliate on margins; obtuse; awned. Awn of upper sterile floret dorsal; 10–12 mm long. Fertile lemma ovate; 4–5 mm long; membranous; keeled; 3 -veined. Lemma margins villous; hairy above. Lemma apex acute; awned; 1 -awned. Principal lemma awn subapical; 6–10 mm long overall. Palea 2 -veined. Palea keels eciliate. Apical sterile florets 1 in number; elliptic; 4 mm long. Apical sterile lemmas pilose (above).

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Africa: west tropical and west-central tropical.

NOTES Cynodonteae. FWTA.

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