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.

Cymbopogon marginatus

HABIT Perennial; caespitose. Butt sheaths pubescent; persistent and investing base of culm; with compacted dead sheaths. Culms erect; 20–70 cm long. Ligule an eciliate membrane; 2 mm long. Leaf-blades 15–35 cm long; 2–5 mm wide; aromatic.

INFLORESCENCE Synflorescence compound; linear; 5–15 cm long; dense. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; enclosed. Spatheole lanceolate; 1.9–4.9 cm long. Peduncle 0.6–2.1 cm long.

Racemes 2; paired; deflexed; 2.8 cm long; bearing 5–7 fertile spikelets on each. Rhachis fragile at the nodes; semiterete; pilose on surface; villous on margins. Rhachis internodes linear; 3 mm long. Rhachis internode tip transverse; cupuliform. Raceme-bases flattened; subequal.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; semiterete; 3 mm long; villous; hairy on surface and margins.

STERILE SPIKELETS Basal sterile spikelets well-developed; 2 in number (lower raceme); 0 in upper raceme; with normal internodes; sessile and pedicelled. Basal sterile spikelet pedicels free; linear. Basal sterile spikelets equalling fertile.

Companion sterile spikelets well-developed; male; lanceolate; 5.5 mm long; as long as fertile; deciduous with the fertile. Companion sterile spikelet glumes chartaceous; distinctly veined; 7 -veined; acute; muticous. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 6 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus base obtuse; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; chartaceous; 2-keeled; keeled all along; keeled laterally; winged on keel; winged moderately. Lower glume intercarinal veins distinct; 2 in number. Lower glume surface flat, or concave. Lower glume apex emarginate. Upper glume lanceolate; 1-keeled. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret hyaline. Fertile lemma lanceolate; hyaline; without keel. Lemma apex lobed; 2 -fid; incised 0.5 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 15 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Anthers 3.

DISTRIBUTION Africa: south.

NOTES Andropogoneae. Soenarko 1993.

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