GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Setaria lachnea

HABIT Perennial; caespitose. Stolons absent, or present. Butt sheaths glabrous, or hirsute. Basal innovations intravaginal. Culms erect, or geniculately ascending, or leaning; 60–150 cm long. Culm-nodes brown; glabrous. Lateral branches lacking, or sparse. Leaf-sheaths antrorsely scabrous; glabrous on surface; outer margin glabrous, or hairy. Ligule a ciliate membrane; 1.8–4 mm long. Leaf-blade base broadly rounded. Leaf-blades linear, or lanceolate; 12–35 cm long; 10–22 mm wide. Leaf-blade midrib conspicuous. Leaf-blade surface hirsute. Leaf-blade margins scabrous. Leaf-blade apex acute.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; continuous, or interrupted; 7–24 cm long; 0.9–3.5 cm wide. Primary panicle branches accrescent to a central axis; with evident branchlets on axis. Panicle axis hirsute.

Spikelets subtended by an involucre. Fertile spikelets sessile; 1 in the cluster. Involucre composed of bristles; 5–12 mm long. Involucral bristles persistent; 1 per spikelet; flexible; antrorsely scaberulous; glabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets ovate; dorsally compressed; 1.9–2.2 mm long; 1–1.3 mm wide; falling entire.

GLUMES Glumes shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.5 length of spikelet; membranous; without keels; 1(–3) -veined. Lower glume lateral veins absent, or obscure. Lower glume apex obtuse, or acute. Upper glume ovate; 0.5–0.75 length of spikelet; membranous; without keels; 5–7 -veined. Upper glume apex cuspidate.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret ovate; 1 length of spikelet; membranous; 5(–7) -veined; cuspidate. Palea of lower sterile floret 0.5–1 length of lemma. Fertile lemma ovate; dorsally compressed; gibbous; 1.9–2.2 mm long; 1–1.3 mm wide; indurate; yellow; without keel. Lemma surface unwrinkled, or rugulose. Lemma margins involute. Lemma apex apiculate. Palea involute; indurate.

FLOWER Lodicules 2; cuneate; 0.3 mm long. Anthers 3.

FRUIT Caryopsis with adherent pericarp; ellipsoid; 1.1–1.3 mm long; yellow. Embryo 0.5 length of caryopsis. Hilum punctiform.

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

NOTES Paniceae. Penseiro 1997.

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