Hyparrhenia nyassae

HABIT Perennial; caespitose. Butt sheaths pubescent, or woolly; with white hairs. Culms erect; 50–150 cm long; 1–4 mm diam. Leaves cauline. Ligule an eciliate membrane; 1–1.5 mm long. Leaf-blades 20–45 cm long; 2–5 mm wide; stiff.

INFLORESCENCE Synflorescence compound; paniculate; 15–45 cm long. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; exserted. Spatheole linear; 3–6 cm long; membranous; brown. Peduncle flexuous; pilose above.

Racemes 2; paired; erect; 2–3 cm long; bearing 4–7 fertile spikelets on each. Rhachis fragile at the nodes; ciliate on margins. Rhachis hairs white. Rhachis internodes linear. Rhachis internode tip oblique; flat. Raceme-bases filiform; unequal (the longer measured); 2–3 mm long; glabrous, or pilose; hairy generally, or at base (white hairs).

Spikelets appressed; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; flattened; ciliate; with white hairs; tip oblique; toothed (0.2–0.5mm).

STERILE SPIKELETS Basal sterile spikelets well-developed; 2 in number (lower raceme); 0 in upper raceme; lanceolate; 5–6 mm long; equalling fertile. Basal sterile spikelet glumes smooth on margins; lower glume muticous.

Companion sterile spikelets well-developed; containing empty lemmas, or male; lanceolate; dorsally compressed; 4.5–7 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; acute; muticous. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 5–6 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate, or linear; 0.8–1.2 mm long; pubescent; base acute; attached obliquely. Spikelet callus hairs white.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of spikelet; coriaceous; mid-green, or purple; without keels; keel-less except near apex. Lower glume surface pubescent. Lower glume hairs yellow. Lower glume apex dentate; 2 -fid. Upper glume linear; coriaceous; without keels.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; 1 length of fertile lemma; hyaline; 2 -veined. Fertile lemma linear; membranous; without keel; 1 -veined. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 20–40 mm long overall; with twisted column. Column of lemma awn pubescent (fulvously); with 0.2–0.5 mm long hairs. Palea absent or minute.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3. Stigmas 2.

DISTRIBUTION Africa: west tropical, west-central tropical, northeast tropical, east tropical, southern tropical, south, and western Indian ocean. Asia-tropical: Indo-China.

NOTES Andropogoneae. WDC.

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