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.

Cenchrus robustus

HABIT Perennial. Cataphylls evident. Rhizomes short. Culms erect; 40–100 cm long; 10–20 -noded. Culm-nodes glabrous. Leaf-sheaths smooth; glabrous on surface; outer margin glabrous, or hairy. Ligule a fringe of hairs; 1–1.5 mm long. Collar glabrous. Leaf-blades 6–22 cm long; 3–7 mm wide. Leaf-blade surface scabrous; glabrous. Leaf-blade margins scabrous; glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; 4–8 cm long. Primary panicle branches accrescent to a central axis; with sessile scars on axis. Panicle axis angular; scabrous; bearing deciduous spikelet clusters.

Spikelets subtended by an involucre. Fertile spikelets sessile; 1–2 in the cluster. Involucre composed of bristles; connate into a disc below; with 0.5 mm connate; elliptic; 9–13 mm long; base bluntly stipitate. Involucral bristles deciduous with the fertile spikelets; numerous; in one whorl; 45–60 in principal whorl; 9–13 mm long; terete; rigid; retrorsely scaberulous; pubescent (below); spinose.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; acuminate; 7.3–9 mm long; 1.5–1.9 mm wide; falling entire; deciduous with accessory branch structures.

GLUMES Glumes shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.9–1.1 mm long; 0.15 length of spikelet; hyaline, or membranous; without keels; (0–)1 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume ovate; 2.8–4.1 mm long; 0.33–0.55 length of spikelet; membranous; without keels; 1–3 -veined. Upper glume lateral veins absent, or obscure. Upper glume surface asperulous. Upper glume apex acute.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret lanceolate; 7.3–9 mm long; 1 length of spikelet; membranous; 5 -veined; distinctly veined; smooth, or scaberulous; rough on veins; acute. Fertile lemma lanceolate; 7.5–9 mm long; coriaceous; much thinner on margins; without keel. Lemma margins flat. Lemma apex acuminate. Palea coriaceous.

FLOWER Anthers 2.9–3.5 mm long.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION Australasia: Australia.

NOTES Paniceae. Webster 1996.

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