Andropogon macrophyllus

HABIT Perennial; caespitose. Culms robust; 200–350 cm long; 6–12 mm diam. Leaf-sheaths outer margin hairy. Ligule a ciliolate membrane; 2–4 mm long. Collar without external ligule. Leaf-blade base tapering to the midrib. Leaf-blades 40–75 cm long; 20–40 mm wide. Leaf-blade apex attenuate.

INFLORESCENCE Synflorescence compound; paniculate; 60–120 cm long; lax. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole. Spatheole lanceolate; 6–10 cm long; scarious, or herbaceous.

Racemes 2; paired; 4–7 cm long. Rhachis fragile at the nodes; glabrous on surface, or pubescent on surface; ciliate on margins. Rhachis hairs 2 mm long. Rhachis internodes clavate; 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 clavate; 4 mm long; ciliate; tip lobed (bilobed).

STERILE SPIKELETS Companion sterile spikelets well-developed; male; oblong; dorsally compressed; 4–5 mm long; shorter than fertile. Companion sterile spikelet glumes chartaceous; acute; mucronate. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 5–6 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pilose; base obtuse; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume oblong; 1 length of spikelet; chartaceous; 2-keeled; keeled laterally. Lower glume intercarinal veins distinct; 8–10 in number. Lower glume surface flat and with a longitudinal median groove. Upper glume lanceolate; membranous; 1-keeled; 3 -veined. Upper glume surface puberulous. Upper glume margins ciliate. Upper glume muticous.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 5 mm long; hyaline; 2 -veined; ciliate on margins. Fertile lemma oblong; 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; 9–16 mm long overall; with twisted column. Column of lemma awn glabrous. Palea oblong.

FLOWER Anthers 3; 4–5 mm long.

DISTRIBUTION Africa: west tropical and west-central tropical.

NOTES Andropogoneae. FTA.

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