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 pampeana

HABIT Perennial. Culms erect, or geniculately ascending; slender; 30–40 cm long. Culm-internodes channelled; antrorsely scabrous; distally pubescent. Culm-nodes pubescent, or bearded. Lateral branches ample; intravaginal. Leaf-sheaths keeled; antrorsely scabrous; outer margin hairy. Ligule a ciliate membrane; 1–1.8 mm long. Leaf-blades flat, or conduplicate; 10–20 cm long; 2–5 mm wide. Leaf-blade surface scabrous; rough on both sides. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; 6–10 cm long; 0.5 cm wide. Primary panicle branches sterile at the tips. Panicle axis angular; scabrous; with scattered hairs, or glabrous. Panicle branches scabrous.

Spikelets subtended by an involucre. Fertile spikelets pedicelled; 1 in the cluster. Involucre composed of bristles; 7–10 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 orbicular; dorsally compressed; acute; 1.8–2 mm long; falling entire.

GLUMES Glumes exceeding apex of florets; thinner than fertile lemma. Lower glume ovate; 0.5 length of spikelet; membranous; without keels; 3 -veined. Lower glume surface glabrous. Lower glume apex acute. Upper glume ovate; 1 length of spikelet; membranous; without keels; 5 -veined. Upper glume lateral veins prominent. Upper glume apex cuspidate.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret ovate; 1 length of spikelet; membranous; 5 -veined; prominently veined; cuspidate. Palea of lower sterile floret 0–5 length of lemma. Fertile lemma orbicular; dorsally compressed; 1.5–1.8 mm long; indurate; without keel. Lemma surface rugulose. Lemma margins involute. Lemma apex apiculate. Palea involute; indurate.

FLOWER Anthers 3; 0.6–0.7 mm long.

FRUIT Caryopsis with adherent pericarp; ovoid; 1–1.2 mm long. Embryo 0.5 length of caryopsis. Hilum punctiform.

DISTRIBUTION South America: western South America and southern South America.

NOTES Paniceae. Fl Pat 1995.

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