Hyparrhenia coriacea

HABIT Annual. Culms erect; 250 cm long. Leaves cauline. Leaf-sheaths mostly shorter than adjacent culm internode; glabrous on surface. Leaf-sheath auricles erect. Ligule an eciliate membrane; 3 mm long. Leaf-blades 40–70 cm long; 7–14 mm wide. Leaf-blade surface glabrous, or puberulous; hairy abaxially.

INFLORESCENCE Synflorescence compound; paniculate. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; enclosed. Spatheole linear; 9 cm long; scarious; glabrous. Peduncle 2.5 cm long; pilose above.

Racemes 2; paired; deflexed; bearing few fertile spikelets; bearing 1 fertile spikelets on each. Rhachis fragile at the nodes. Rhachis internodes linear. Rhachis internode tip oblique; flat. Raceme-bases flattened; subequal.

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

STERILE SPIKELETS Basal sterile spikelets well-developed; on lower raceme 4 in number; 4 in upper raceme; forming an involucre about the fertile; lanceolate; 13–17 mm long; equalling fertile. Basal sterile spikelet lower glume muticous.

Companion sterile spikelets well-developed; lanceolate; dorsally compressed; separately deciduous. Companion sterile spikelet glumes chartaceous; acute.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong, or oblanceolate; dorsally compressed; 10–15 mm long; 2 mm wide; falling entire; deciduous with accessory branch structures. Spikelet callus linear; 3.5–4.5 mm long; pilose; base pungent; attached obliquely.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; coriaceous; without keels; 9–11 -veined. Lower glume surface pubescent. Lower glume hairs white; 1 mm long. Upper glume linear; coriaceous; without keels; 3 -veined. Upper glume primary vein scaberulous. Upper glume surface pubescent. Upper glume margins ciliolate. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; hyaline; 2 -veined; ciliolate on margins; dentate; 2 -fid. Fertile lemma linear; membranous; without keel. Lemma apex dentate; 2 -fid; with lobes 1–1.5 mm long; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 120–160 mm long overall; with twisted column. Column of lemma awn pubescent; with 1–1.2 mm long hairs. Palea 2–2.6 mm long.

FRUIT Caryopsis oblong; dorsally compressed; 6.5–7.5 mm long.

DISTRIBUTION Africa: west-central tropical.

NOTES Andropogoneae. Mazade 2005.

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