Diheteropogon amplectens

HABIT Perennial. Cataphylls evident. Rhizomes short. Culms 30–100 cm long. Ligule an eciliate membrane. Leaf-blade base simple, or broadly rounded, or cordate. Leaf-blades flat, or convolute; 15–30 cm long; 2–25 mm wide. Leaf-blade apex attenuate; filiform.

INFLORESCENCE Synflorescence compound; scanty. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole. Spatheole lanceolate; 7–8 cm long; herbaceous.

Racemes 2; paired; 5–14(–17) cm long. Rhachis fragile at the nodes; ciliate on margins. Rhachis internodes linear. Rhachis internode tip crateriform; with simple rim. Raceme-bases filiform.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; ciliate.

STERILE SPIKELETS Basal sterile spikelets well-developed; 2 in number (lower raceme); 0 in upper raceme; equalling fertile.

Companion sterile spikelets well-developed; male; lanceolate; dorsally compressed; 9–13 mm long; longer than fertile; deciduous with the fertile. Companion sterile spikelet glumes herbaceous; wingless; muticous, or awned; one glume awned; with 0–8 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 linear; dorsally compressed; 6–9 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus linear; 1–2 mm long; pilose; base pungent; inserted.

GLUMES Glumes dissimilar; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; coriaceous; 2-keeled; keeled dorsally; keeled obtusely. Lower glume lateral veins several in each keel. Lower glume surface with a longitudinal median groove, or deeply depressed. Lower glume apex dentate; 2 -fid. Upper glume 3 -veined. Upper glume margins ciliate.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret hyaline; 2 -veined; ciliate on margins. Fertile lemma linear; hyaline; without keel; 3 -veined. Lemma margins ciliate; hairy above. Lemma apex dentate; 2 -fid; incised 0.2 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; bigeniculate; 25–70 mm long overall; with twisted column. Column of lemma awn hispidulous, or pubescent. Palea hyaline; 2 -veined. Palea keels ciliolate.

DISTRIBUTION Africa: west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, and south.

NOTES Andropogoneae. FTEA.

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