GrassBase - The Online World Grass Flora


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

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

Ctenium longiglume

HABIT Perennial; caespitose. Culms erect; 120–140 cm long. Leaf-sheaths antrorsely scabrous. Ligule an eciliate membrane; 1.5–2.5 mm long; obtuse. Leaf-blades 20–30 cm long; 1.2–2.5 mm wide. Leaf-blade surface scabrous; rough on both sides.

INFLORESCENCE Inflorescence composed of racemes. Peduncle pubescent above.

Racemes 1; single; unilateral; (10–)13–19 cm long; 12–14 mm wide. Rhachis scabrous on surface; glabrous on surface to pubescent on surface; 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; (3.5–)7–8 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; dissimilar; exceeding apex of florets; firmer than fertile lemma; gaping. Lower glume lanceolate; 2–3.2 mm long; 0.3–0.4 length of upper glume; herbaceous; 1-keeled; 1 -veined. Lower glume primary vein tuberculate. Lower glume lateral veins absent. Lower glume surface scabrous. Lower glume apex acuminate, or attenuate. Upper glume lanceolate; (5.5–)7–8 mm long; 1.7–1.8 length of adjacent fertile lemma; herbaceous; 1-keeled; 2 -veined. Upper glume primary vein tuberculate. Upper glume surface scabrous; hirsute; hairy below. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn dorsal and oblique; (3.5–)3.8–4.5(–7.5) mm long.

FLORETS Basal sterile florets dissimilar; male (sometimes the upper), or barren; with palea (the upper), or without significant palea; attached to and deciduous with the fertile. Lemma of lower sterile floret lanceolate; 2.5–3 mm long; 0.7–0.8 length of fertile lemma; membranous; 1-keeled; glabrous; ciliate on margins; bearing hairs 1–2.3 mm long; emarginate, or truncate; awned. Awn of lower sterile floret subapical; (5–)7–7.8 mm long. Lemma of upper sterile floret lanceolate; 3–4 mm long; 1.2–1.3 length of lower sterile floret; membranous; glabrous; ciliate on margins; fringed above; emarginate, or obtuse; awned. Awn of upper sterile floret terminal, or subapical; (9–)11–12 mm long. Fertile lemma lanceolate; 4–4.2(–4.8) mm long; 0.6–0.7 mm wide; membranous; keeled; 3 -veined. Lemma margins ciliate; hairy above. Lemma hairs 1.5–2 mm long. Lemma apex acute; awned; 1 -awned. Principal lemma awn subapical; (2.8–)3.5–4.5 mm long overall. Palea 3.5–3.8 mm long; 2 -veined. Apical sterile florets 2 in number; male, or barren; separate; linear; 1.5–4 mm long. Apical sterile lemmas muticous, or mucronate.

DISTRIBUTION Africa: west-central tropical and southern tropical.

NOTES Cynodonteae. L-W & Cope 2003.

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