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 rukwae

HABIT Perennial. Rhizomes elongated; scaly. Butt sheaths glabrous, or pubescent. Culms 25–120 cm long; spongy. Culm-nodes glabrous. Ligule an eciliate membrane. Leaf-blades 5–30 cm long; 2–7 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 6–25; borne along a central axis; simply spaced, or in several whorls; unilateral; 4–10 cm long. Central inflorescence axis 4–20 cm long. Rhachis wingless; angular.

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 elliptic; dorsally compressed; 2–2.6 mm long; with hairs extending 0 mm beyond apex; falling entire.

GLUMES Glumes two; dissimilar; reaching apex of florets, or shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.1–0.5 mm long; 0.05–0.2 length of spikelet; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex obtuse. Upper glume elliptic; 0.75–1 length of spikelet; membranous; without keels; 3(–5) -veined. Upper glume surface pubescent, or pilose. 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; pubescent, or pilose; acute. Fertile lemma elliptic; 2–2.5 mm long; cartilaginous; much thinner on margins; light brown; without keel. Lemma margins flat; covering most of palea. Lemma apex acute. Palea cartilaginous.

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

NOTES Paniceae. FTEA.

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