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.

Setaria setosa

HABIT Perennial. Culms erect, or geniculately ascending; 50–100 cm long; firm, or woody. Culm-internodes smooth. Culm-nodes glabrous. Leaf-sheaths glabrous on surface, or puberulous; outer margin hairy. Ligule a fringe of hairs; 1 mm long. Collar glabrous, or pubescent. Leaf-blades flat, or conduplicate; 15–20 cm long; 6–12 mm wide. Leaf-blade surface scabrous; rough adaxially; glabrous, or puberulous; hairy on both sides.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; lanceolate; interrupted; loose; 15–20 cm long. Primary panicle branches ascending; 0.5–2.5 cm long; sterile at the tips. Panicle axis angular; scabrous; glabrous, or villous.

Spikelets subtended by an involucre. Fertile spikelets pedicelled; 1 in the cluster. Involucre composed of bristles; 5–10 mm long. Involucral bristles persistent; 1 per spikelet; flexible; antrorsely scaberulous; glabrous. Pedicels oblong.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; 2–2.5 mm long; falling entire.

GLUMES Glumes shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.5 length of spikelet; membranous; without keels; 3 -veined. Lower glume apex acute. Upper glume ovate; 0.66 length of spikelet; membranous; without keels; 5–7 -veined. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret ovate; 1 length of spikelet; membranous; 5 -veined; acute. Palea of lower sterile floret 1 length of lemma. Fertile lemma ovate; dorsally compressed; gibbous; 2–2.5 mm long; indurate; without keel. Lemma surface rugulose. Lemma margins involute. Lemma apex apiculate. Palea involute; indurate.

DISTRIBUTION North America: Mexico. South America: Caribbean, northern South America, western South America, Brazil, and southern South America.

NOTES Paniceae. Rominger 1994.

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