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.

Pennisetum laxius

HABIT Annual. Culms erect, or geniculately ascending; 40–80 cm long; 7–10 -noded. Lateral branches ample. Leaf-sheaths glabrous on surface, or pilose. Ligule a ciliate membrane. Leaf-blade base without a false petiole, or with a false petiole; petiole 0–5 cm long. Leaf-blades 5–10(–25) cm long; 3–6(–14) mm wide; flaccid. Leaf-blade surface pubescent, or pilose. Leaf-blade margins scaberulous. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle; terminal and axillary.

Panicle spiciform; linear; 2–3 cm long. Primary panicle branches accrescent to a central axis; with lateral stumps on axis. Panicle axis scaberulous; glabrous.

Spikelets subtended by an involucre. Fertile spikelets sessile; 1 in the cluster. Involucre composed of bristles; base obtuse. Involucral bristles deciduous with the fertile spikelets; in one whorl; 1 in principal whorl; 15–25 mm long; terete; flexible; glabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; acuminate; (3–)3.5–4(–4.5) mm long; falling entire; deciduous with accessory branch structures. Spikelet callus base truncate.

GLUMES Glumes similar; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.5 mm long; 0.5 length of upper glume; 0.1–0.15 length of spikelet; hyaline; pallid; without keels; 0 -veined. Lower glume lateral veins absent. Lower glume apex emarginate, or truncate, or obtuse. Upper glume elliptic; 0.75–1 mm long; 0.2–0.25 length of spikelet; hyaline; pallid; without keels; 0 -veined. Upper glume primary vein absent. Upper glume apex emarginate, or truncate, or obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret ovate; 1 length of spikelet; membranous; 5 -veined; spinulose; rough above; hispidulous; hairy above; hairy between veins; acuminate. Fertile lemma elliptic; 3–4 mm long; cartilaginous; without keel; 5 -veined. Lemma surface hispidulous; hairy above. Lemma margins flat. Lemma apex acute. Palea 1 length of lemma; cartilaginous; 2 -veined.

FLOWER Lodicules 2; cuneate; 0.2 mm long; truncate. Anthers 3; 2 mm long.

DISTRIBUTION Africa: west tropical and west-central tropical.

NOTES Paniceae. WDC.

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