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 arenicola

HABIT Perennial; caespitose; clumped loosely. Rhizomes elongated. Culms 30–60 cm long. Culm-nodes glabrous, or pubescent. Leaves cauline. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; 0.4–1 mm long; entire, or lacerate; truncate. Leaf-blades flat, or conduplicate; 5–11.5 cm long; 3–4.5 mm wide. Leaf-blade surface glabrous.

INFLORESCENCE Inflorescence a panicle; terminal and axillary; deciduous as a whole.

Panicle open; ovate; effuse; 12–24 cm long; 19–40 cm wide. Primary panicle branches spreading; 20–21 cm long. Panicle branches capillary; straight.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 3.5–4.6 mm long; 0.8–1 mm wide; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.2–0.5 mm long; 0.05–0.1 length of spikelet; hyaline. Upper glume elliptic; 3–3.8 mm long; 1 length of spikelet; membranous; 5–7 -veined. Upper glume surface glabrous to villous; hairy between veins. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 3–3.8 mm long; 1 length of spikelet; membranous; 5–7 -veined; pubescent to villous; hairy between veins; acute. Fertile lemma elliptic; 3–3.7 mm long; cartilaginous; much thinner on margins; dark brown; without keel. Lemma margins flat; covering most of palea. Lemma apex acute. Palea cartilaginous.

FLOWER Anthers 1.1–1.4 mm long.

FRUIT Caryopsis with adherent pericarp; 1.5–2 mm long.

DISTRIBUTION North America: south-central USA.

NOTES Paniceae. Fl N Amer 2007.

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