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.

Digitaria acuminatissima

HABIT Annual. Culms decumbent; robust; 60–120 cm long; rooting from lower nodes. Ligule an eciliate membrane. Leaf-blades 3–25 cm long; 3–10 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 4–20; digitate, or borne along a central axis; straight; unilateral; 7–25 cm long. Central inflorescence axis 1–10 cm long. Rhachis broadly winged; with sharp-edged midrib. Spikelet packing 0.66 their length apart.

Spikelets in pairs. Fertile spikelets pedicelled; 2 in the cluster. Pedicels unequal.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate, or elliptic; dorsally compressed; acuminate; 2.5–4 mm long; falling entire.

GLUMES Glumes two; dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.2–0.4 mm long; 0.05–0.1 length of spikelet; hyaline; without keels; 0 -veined. Lower glume lateral veins absent. Lower glume apex obtuse. Upper glume lanceolate; 0.33–0.5 length of spikelet; membranous; without keels; 3 -veined. Upper glume surface pubescent. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 1 length of spikelet; membranous; 7 -veined; with equidistant veins; scaberulous; rough on veins; pubescent and setose (sometimes); acuminate. Fertile lemma lanceolate; 2.3–3.5 mm long; cartilaginous; much thinner on margins; pallid, or grey; without keel. Lemma margins flat; covering most of palea. Lemma apex acuminate. Palea cartilaginous.

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

NOTES Paniceae. FTEA.

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