Digitaria filiformis

HABIT Annual; caespitose. Culms erect; 50–80 cm long. Leaf-sheaths hirsute. Ligule an eciliate membrane; 1 mm long. Leaf-blades 10–25 cm long; 2–6 mm wide. Leaf-blade surface glabrous, or puberulous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1–5; single, or paired, or borne along a central axis; unilateral; 7–13 cm long. Central inflorescence axis 5–7 cm long. Rhachis angular.

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

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 1.5–1.9 mm long; falling entire.

GLUMES Glumes one the lower absent or obscure; shorter than spikelet; thinner than fertile lemma. Upper glume elliptic; 0.75 length of spikelet; membranous; without keels; 3 -veined. Upper glume surface glabrous, or puberulous; with capitate hairs. Upper glume margins 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; glabrous, or puberulous; with capitate hairs; pubescent on margins; acute. Fertile lemma oblong, or ovate; 1.5–1.9 mm long; cartilaginous; much thinner on margins; dark brown; without keel. Lemma surface scaberulous. Lemma margins flat; covering most of palea. Lemma apex acute. Palea cartilaginous.

DISTRIBUTION North America: north-central USA, northeast USA, south-central USA, southeast USA, and Mexico. South America: western South America, Brazil, and southern South America.

NOTES Paniceae. Gr Texas 1993.

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