Hyparrhenia madaropoda

HABIT Annual. Butt sheaths glabrous. Culms erect, or decumbent; robust; 100–300 cm long; 3–5 mm diam.; with prop roots. Leaves cauline. Leaf-sheath auricles erect; 5–10 mm long. Ligule an eciliate membrane; 10–25 mm long. Leaf-blade base with a false petiole. Leaf-blades 20–45 cm long; 7–13 mm wide. Leaf-blade surface glabrous.

INFLORESCENCE Synflorescence compound; paniculate; 25–35 cm long. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; enclosed. Spatheole lanceolate; 2.5–4 cm long; membranous. Peduncle deflexed; 0.3–0.5 cm long; pilose above (on one side).

Racemes 2; paired; appressed; 1.5 cm long; bearing few fertile spikelets; bearing 1 fertile spikelets on each. Rhachis fragile at the nodes; ciliate on margins. Rhachis internodes linear. Rhachis internode tip oblique; flat. Raceme-bases linear; subequal; 2–2.5 mm long; stiffly setose; shortly lobed; with 0.5–0.7 mm long appendage.

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

STERILE SPIKELETS Basal sterile spikelets well-developed; on lower raceme 2 in number; 0 in upper raceme; lanceolate; 8–9 mm long; equalling fertile. Basal sterile spikelet glumes glabrous; smooth on margins; lower glume muticous.

Companion sterile spikelets well-developed; containing empty lemmas, or male; lanceolate; dorsally compressed; 8–9 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; acute; muticous, or awned; one glume awned; with 0–6 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 lanceolate; dorsally compressed; 7–9.5 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus cuneate; 1.5–3 mm long; pubescent; 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; keel-less except near apex. Lower glume surface glabrous, or hispidulous. 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; 45–65 mm long overall; with twisted column. Column of lemma awn pubescent. Palea absent or minute.

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

DISTRIBUTION Africa: northeast tropical, east tropical, and southern tropical.

NOTES Andropogoneae. WDC.

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