Pennisetum thunbergii

HABIT Perennial; caespitose. Rhizomes elongated. Butt sheaths glabrous. Culms erect, or geniculately ascending; 10–150 cm long. Leaf-sheaths glabrous on surface. Ligule a fringe of hairs. Leaf-blades flat, or convolute; 3–40 cm long; 2–8 mm wide. Leaf-blade apex attenuate; filiform.

INFLORESCENCE Inflorescence a panicle. Peduncle glabrous.

Panicle spiciform; linear, or oblong; 2–15 cm long. Primary panicle branches accrescent to a central axis; with lateral stumps on axis. Panicle axis with rounded ribs; scaberulous; glabrous; bearing deciduous spikelet clusters.

Spikelets subtended by an involucre. Fertile spikelets sessile; 1 in the cluster. Involucre composed of bristles; oblong; 5–14 mm long; base truncate. Involucral bristles deciduous with the fertile spikelets; numerous; with longest bristle scarcely emergent; 5–14 mm long; terete; flexible; glabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate, or ovate; dorsally compressed; acuminate; 2.5–5 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 oblong, or ovate; 0.2–0.25 length of spikelet; hyaline; without keels; 0–1 -veined. Upper glume primary vein absent, or distinct. Upper glume lateral veins absent. Upper glume apex emarginate, or obtuse, or acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic, or ovate; (0.25–)0.33–0.66(–0.75) length of spikelet; membranous; 1–3 -veined; cuspidate, or acuminate; mucronate. Awn of lower sterile floret 0.5–1.5 mm long. Fertile lemma ovate; 2.5–5 mm long; membranous; without keel; 5–7 -veined. Lemma margins flat. Lemma apex acuminate; muticous, or mucronate. Palea 1 length of lemma; membranous.

FLOWER Lodicules absent. Anthers 3; 1.5–2.5 mm long; anther tip smooth, or penicillate. Styles connate below; 0.2 of their length connate.

FRUIT Caryopsis with adherent pericarp; oblong; dorsally compressed; 1.7 mm long.

DISTRIBUTION Africa: west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, and south. Asia-temperate: Arabia. Asia-tropical: India. Australasia: Australia.

NOTES Paniceae. FTEA.

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