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 megasthenes

HABIT Perennial; caespitose. Cataphylls evident. Rhizomes short. Culms erect, or geniculately ascending; 70–110 cm long. Culm-nodes brown; glabrous. Leaf-sheaths antrorsely scabrous. Ligule a ciliolate membrane; 2–3 mm long. Leaf-blades 4–15 cm long; 2–7 mm wide. Leaf-blade surface scabrous; rough on both sides. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 5–11; digitate; in several whorls; erect; unilateral; 4–12 cm long. Rhachis broadly winged; with sharp-edged midrib; 0.5 mm wide; smooth on surface, or scabrous on surface; scabrous on margins.

Spikelets in pairs. Fertile spikelets pedicelled; 2 in the cluster. Pedicels angular; unequal; 0.5–1.5 mm long; scabrous; tip widened.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 1.9–2.5 mm long; falling entire.

GLUMES Glumes two; dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.1 length of spikelet; hyaline; without keels; 0 -veined. Lower glume lateral veins absent. Lower glume apex truncate, or acute. Upper glume ovate; 0.2–0.5 length of spikelet; membranous; without keels; 0–3 -veined. Upper glume surface scabrous; rough generally; glabrous. Upper glume apex entire, or dentate; 2 -fid; acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret oblong; 1 length of spikelet; membranous; 7(–9) -veined; without grooves, or sulcate; scabrous; rough throughout; glabrous, or setose; acute. Fertile lemma oblong; 1.9–2.5 mm long; cartilaginous; much thinner on margins; yellow; without keel. Lemma margins flat; covering most of palea. Lemma apex acute. Palea cartilaginous.

DISTRIBUTION Africa: southern tropical.

NOTES Paniceae. FZ.

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