Digitaria humbertii

HABIT Perennial; mat forming. Stolons present. Culms decumbent, or rambling; slender; 10–30 cm long; rooting from lower nodes. Culm-internodes distally glabrous. Ligule an eciliate membrane; 0.5 mm long; truncate. Leaf-blades 2–5 cm long; 1.5–4 mm wide. Leaf-blade surface glabrous, or pubescent, or hirsute; densely hairy.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2–4; paired, or digitate; unilateral; 2–6 cm long. Rhachis angular.

Spikelets ascending; solitary, or in pairs. Fertile spikelets pedicelled; 1–2 in the cluster. Pedicels unequal; 0.5–2 mm long.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong, or ovate; dorsally compressed; acute; 2–2.2 mm long; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.25–0.5 length of spikelet; membranous; much thinner on margins; without keels; 0 -veined. Lower glume lateral veins absent. Lower glume apex obtuse. Upper glume ovate; 1 length of spikelet; membranous; 5 -veined. Upper glume surface glabrous. 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; glabrous; acute. Fertile lemma oblong; 2–2.2 mm long; cartilaginous; much thinner on margins; yellow, or purple; without keel. Lemma margins flat; covering most of palea. Lemma apex acute. Palea cartilaginous.

DISTRIBUTION Africa: western Indian ocean.

NOTES Paniceae. Gr Madag 1997.

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