Andropogon chevalieri

HABIT Annual; caespitose. Culms 200–250 cm long. Leaf-sheath auricles erect; 3–10 mm long. Ligule an eciliate membrane; 3–10 mm long. Leaf-blade base tapering to the midrib. Leaf-blades 20–40 cm long; 2–8 mm wide.

INFLORESCENCE Synflorescence compound; paniculate; 6–20 cm long; lax. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; embraced at base by subtending leaf. Spatheole lanceolate; 5–8 cm long.

Racemes 2; paired; 4–6 cm long. Rhachis fragile at the nodes; puberulous on surface; ciliate on margins. Rhachis internodes filiform; 4 mm long. Rhachis internode tip transverse; crateriform; with simple rim.

Spikelets appressed; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels cuneate; 3 mm long; puberulous (on margins, pubescent on surface); tip lobed (bilobed).

STERILE SPIKELETS Companion sterile spikelets well-developed; containing empty lemmas, or male; elliptic; dorsally compressed; 5–10 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; 12 -veined; glabrous, or pubescent; acute; awned; one glume awned; with 5–10 mm long awn. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 5.5–10 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus square; 1 mm long; pubescent; base obtuse; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume elliptic; 1 length of spikelet; coriaceous; 2-keeled; keeled laterally. Lower glume primary vein scabrous. Lower glume surface convex and with a longitudinal median groove; pubescent; hairy in lines (along midline). Lower glume apex acute. Upper glume elliptic; chartaceous; 1-keeled; 3 -veined. Upper glume surface pubescent. Upper glume apex truncate; mucronate.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 6–7 mm long; hyaline; 2 -veined; ciliate on margins. Fertile lemma oblong; 5 mm long; hyaline; without keel; 1 -veined. Lemma apex lobed; 2 -fid; incised 0.33 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 18–25 mm long overall; with twisted column. Column of lemma awn glabrous. Palea 0.75 length of lemma.

FLOWER Anthers 3; 3 mm long.

DISTRIBUTION Africa: west tropical.

NOTES Andropogoneae. FWTA.

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