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 chacoensis

HABIT Perennial; caespitose. Butt sheaths sparsely hairy. Culms robust; 50–70 cm long. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; truncate. Leaf-blades filiform; convolute; 1–2 mm wide; stiff. Leaf-blade surface ribbed; grooved adaxially.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 3; digitate; unilateral; 10–15 cm long. Rhachis angular.

Spikelets in threes. Fertile spikelets pedicelled; 3 in the cluster. Pedicels angular; unequal; 1–5 mm long; scabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 4.2–4.5 mm long; 0.6 mm wide; falling entire.

GLUMES Glumes shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.5 mm long; 0.1 length of spikelet; hyaline; 0 -veined. Lower glume lateral veins absent. Lower glume apex obtuse. Upper glume lanceolate; 2.5–2.7 mm long; 0.66 length of spikelet; membranous; without keels; 3 -veined. Upper glume surface puberulous; hairy between veins. Upper glume apex acute.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret lanceolate; 1 length of spikelet; membranous; 7 -veined; with unevenly spaced veins; puberulous; pubescent on margins; acute. Palea of lower sterile floret 0.7 mm long. Fertile lemma elliptic; 4.2–4.5 mm long; cartilaginous; much thinner on margins; dark brown; without keel. Lemma surface striate. Lemma margins flat; covering most of palea. Lemma apex acuminate. Palea 1 length of lemma; cartilaginous.

FLOWER Lodicules 2; 0.3–0.4 mm long. Anthers 3; 1.75 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION South America: southern South America.

NOTES Paniceae. Rugulo 1997.

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