Poaceae
Setaria

Setaria lachnea (Nees) Kunth

First published in Enum. Pl. 1: 154 (1833)
This species is accepted
The native range of this species is Peru to S. Brazil and N. Argentina. It is a perennial and grows primarily in the subtropical biome.

Descriptions

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: not threatened. Confidence: confident
[AERP]

Morphology General 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.
Morphology Reproductive morphology Inflorescences
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.
Morphology Reproductive morphology Inflorescences 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.
Fertile
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.
Morphology Reproductive morphology Inflorescences Bracts Glume
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.
Morphology Reproductive morphology Flowers 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.
Morphology Reproductive morphology Flowers
Lodicules 2; cuneate; 0.3 mm long. Anthers 3.
Morphology Reproductive morphology Fruits
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.
Reference
Paniceae. Penseiro 1997.
[GB]

Sources

  • Angiosperm Extinction Risk Predictions v1

    • Angiosperm Threat Predictions
    • http://creativecommons.org/licenses/by/4.0

  • GrassBase - The Online World Grass Flora

    • Clayton, W.D., Vorontsova, M.S., Harman, K.T. and Williamson, H. (2006 onwards). GrassBase - The Online World Grass Flora.
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • Herbarium Catalogue Specimens

    • Digital Image © Board of Trustees, RBG Kew http://creativecommons.org/licenses/by/3.0/

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2026. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2026. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0