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 melanostachyus

HABIT Perennial. Rhizomes short. Culms geniculately ascending; 40–60 cm long; swollen at the base. Culm-internodes smooth; distally glabrous. Leaf-sheaths keeled; pilose. Ligule a fringe of hairs; 0.5 mm long. Leaf-blades 25–35 cm long; 4–5 mm wide. Leaf-blade surface scaberulous; hirsute; sparsely hairy. Leaf-blade margins smooth, or scaberulous. Leaf-blade apex acute.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; 3–8 cm long; 0.7–1.2 cm wide. Primary panicle branches accrescent to a central axis; with sessile scars on axis. Panicle axis angular; scaberulous; bearing deciduous spikelet clusters.

Spikelets subtended by an involucre. Fertile spikelets sessile; 3 in the cluster. Involucre composed of bristles; connate into a disc below; with 1 mm connate; 6–7 mm long. Involucral bristles deciduous with the fertile spikelets; with an outer whorl of thinner bristles; inner bristles longer than outer; with longest bristle scarcely emergent, or with one conspicuously longer bristle; 5–8 mm long; flattened; rigid; antrorsely scaberulous; glabrous; spinose.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; acuminate; 4.5 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes one the lower absent or obscure; shorter than spikelet; thinner than fertile lemma. Upper glume ovate; 1.8–2 mm long; 0.4–0.5 length of spikelet; membranous; without keels; 1 -veined. Upper glume lateral veins absent. Upper glume surface puberulous.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret lanceolate; 1 length of spikelet; membranous; 5 -veined; puberulous; hairy above; acuminate. Fertile lemma ovate; 4.5 mm long; coriaceous; much thinner on margins; without keel; 5 -veined. Lemma margins flat. Lemma apex acuminate; pubescent. Palea coriaceous.

FLOWER Anthers 3; 2.5 mm long; yellow.

FRUIT Caryopsis with adherent pericarp; ovoid; dorsally compressed; 2.5 mm long.

DISTRIBUTION Africa: western Indian ocean.

NOTES Paniceae. Camus 2007.

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