GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Hyparrhenia pilosa

HABIT Perennial. Culms erect; 150 cm long. Leaves cauline. Leaf-sheaths mostly shorter than adjacent culm internode. Ligule an eciliate membrane; 3 mm long. Leaf-blades 25–45 cm long; 3–6 mm wide.

INFLORESCENCE Synflorescence compound; paniculate. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; enclosed. Spatheole linear; 7–8 cm long; membranous. Peduncle pilose above.

Racemes 2; paired; deflexed; 2.3 cm long; bearing few fertile spikelets; bearing 2–4 fertile spikelets on each. Rhachis fragile at the nodes; villous on margins. Rhachis hairs red; 2–3 mm long. Rhachis internodes linear. Rhachis internode tip oblique; flat. Raceme-bases filiform; unequal (the longer measured); 2–2.5 mm long; pilose.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; 3.5–4 mm long; villous; with red hairs; with 2–3 mm long hairs; tip oblique; toothed (0.3–0.6 mm).

STERILE SPIKELETS Basal sterile spikelets well-developed; on lower raceme 2 in number; 2 in upper raceme; lanceolate; 5.5–7.5 mm long; smaller than fertile. Basal sterile spikelet glumes hirsute; with red hairs; lower glume muticous.

Companion sterile spikelets well-developed; lanceolate; dorsally compressed; 6–8 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; 13–15 -veined; hirsute; acute; muticous, or mucronate.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate, or oblong; dorsally compressed; 7–9 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus linear; 2–2.5 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 hirsute. Lower glume hairs red; 3–4 mm long. Lower glume apex truncate. Upper glume lanceolate; coriaceous; without keels. Upper glume surface hirsute; hairy above. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; hyaline; 2 -veined; ciliate on margins; fringed above; truncate. Fertile lemma linear; membranous; without keel. Lemma margins ciliolate. Lemma apex dentate; 2 -fid; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 40–75 mm long overall; with twisted column. Column of lemma awn ciliate (rufously); with 2 mm long hairs.

DISTRIBUTION Africa: west-central tropical.

NOTES Andropogoneae. Mazade 2005.

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