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 newtonii

HABIT Perennial; caespitose. Glands wart-like. Culms erect; 50–100 cm long; wiry. Ligule an eciliate membrane; erose. Leaf-blades involute; 5–25 cm long; 2–4 mm wide; aromatic.

INFLORESCENCE Inflorescence composed of racemes. Peduncle pubescent above (at tip).

Racemes 1; single; straight, or corkscrew spiralled; unilateral; (5–)7–20(–30) cm long. Rhachis semiterete; glabrous on surface; pubescent 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; 4–7 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pilose.

GLUMES Glumes persistent; dissimilar; exceeding apex of florets; firmer than fertile lemma; gaping. Lower glume lanceolate; 0.3–0.5 length of upper glume; herbaceous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex acuminate; mucronate. Upper glume lanceolate; 4–7 mm long; 1.75–2 length of adjacent fertile lemma; herbaceous; with hyaline margins; glandular; 1-keeled; 2 -veined. Upper glume primary vein tuberculate. Upper glume surface hispidulous. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn dorsal and oblique; 1–2 mm long.

FLORETS Basal sterile florets dissimilar; barren; without significant palea; attached to and deciduous with the fertile. Lemma of lower sterile floret elliptic, or oblong; 1.5–2 mm long; 0.5–0.75 length of fertile lemma; membranous; 1-keeled; glabrous, or puberulous (sparsely); hairy between veins; ciliate on midvein; ciliate on margins; obtuse; awned. Awn of lower sterile floret subapical. Lemma of upper sterile floret ovate; 2–2.5 mm long; membranous; glabrous; eciliate on midvein, or ciliate on midvein; ciliate on margins; obtuse; awned. Awn of upper sterile floret dorsal (with an oblong tongue above insertion). Fertile lemma ovate; 2–4 mm long; membranous; keeled; 3 -veined. Lemma margins ciliate. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn subapical; 2.5–3 mm long overall. Palea 2 -veined. Palea keels ciliolate. Apical sterile florets 2 in number; separate; linear; 1–2.5 mm long. Apical sterile lemmas awned; 1 -awned.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Africa: west tropical, west-central tropical, northeast tropical, east tropical, and southern tropical.

NOTES Cynodonteae. FWTA.

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