Amaranthus floridanus (S.Watson) J.D.Sauer (1955:25)
Florida amaranth
Taxonomy & Nomenclature
Synonym/s: Acnida floridana S.Watson in Proc. Amer. Acad. Arts 17: 376 (1882)
Conservation Status
Possibly Extinct in the Wild (Gann et al. 2001-2025; NatureServe, 2026)
Last (wild) record: 1985 (Gann et al., 2002:113,115 [as global]); 1989 (as wild) (Gann et al. 2001-2025; NatureServe, 2026)
Rediscovered in the wild/last wild record: 2024 (Gann et al. 2001-2025; NatureServe, 2026)
This species was previously reported as globally extinct by the Floristic Inventory of South Florida (Gann et al., 2001-2023 fide Possley et al., 2024), before a single male plant was found in 2024 in a parking lot associated with a restaurant on Lido Key by Alan Franck (Gann et al., 2001-2025; NatureServe, 2026). However, 200 seeds were collected in 1989 (USDA, 2025), and which has resulted in a population in cultivation (Gann et al., 2001-2025; SEINet, 2025), but knowledge of this is not ubiquitous (e.g. Gann et al., 2002:113-115; Weakley & SFT, 2026).
Distribution & Habitat
Florida, USA
Anatomy & Morphology
Biology & Ecology
Hypodigm
Media
References
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Gann, George D., Bradley, Keith A. and Woodmansee, Steven W. (2002). Rare Plants of South Florida: Their History, Conservation, and Restoration. Miami, Florida: The Institute for Regional Conservation. xiv + 1056 pp.
Gann, George D., Trotta, L. B., and Collaborators. (2001-2023). Floristic Inventory of South Florida Database [web application]. The Institute for Regional Conservation. Delray Beach, FL, U.S.A. Available at: www.regionalconservation.org/ircs/database/Database.asp [Accessed by Possley et al., 2024 in May 2023]
Gann, George D., Trotta, L. B., and Collaborators. (2001-2025). Amaranthus floridanus (S. Watson) Sauer: Florida amaranth. In: Floristic Inventory of South Florida Database Online. The Institute for Regional Conservation. Delray Beach, Florida. Available at: https://www.regionalconservation.org/ircs/database/database.asp [Accessed 21 August 2026]
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NatureServe. (2026). Amaranthus floridanus: Florida Amaranth. NatureServe Network Biodiversity Location Data accessed through NatureServe Explorer [web application]. NatureServe, Arlington, Virginia. Available at: https://explorer.natureserve.org/ [Accessed on 20 August 2026]
Nolan, C., Noyes, A., Bennett, A., Hunter, R. and Hunter, K. L. (2010). Inter simple sequence repeats (ISSR) reveal genetic variation among Mid-Atlantic populations of threatened Amaranthus pumilus and phylogenetic relationships. Castanea 75(4): 506-516. https://doi.org/10.2179/09-050.1
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USDA (United States Department of Agriculture). (2025). PI 553078, Amaranthus floridanus (S. Watson) J. D. Sauer, DB 8916. In: USDA National Plant Germplasm System. Available at: https://npgsweb.ars-grin.gov/gringlobal/accessiondetail?id=1448050 [Accessed 21 August 2026]
Waselkov, K. E., Boleda, A. S. and Olsen, K. M. (2018). A phylogeny of the genus Amaranthus (Amaranthaceae) based on several low-copy nuclear loci and chloroplast regions. Syst. Bot. 43: 439-458. https://doi.org/10.1600/036364418X697193
Weakley, A. S. and SFT (Southeastern Flora Team). (2026). Amaranthus floridanus (S. Watson) Sauer. In: Flora of the southeastern United States Web App. University of North Carolina Herbarium, North Carolina Botanical Garden, Chapel Hill, U.S.A. https://fsus.ncbg.unc.edu/main.php?pg=show-taxon-detail.php&lsid=urn:lsid:ncbg.unc.edu:taxon:{57784F16-8A78-4BFA-92D6-827CC68C9BC8}&tempaccesskey=337167901. Accessed Aug 21, 2026.
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