Cirsium praeteriens J.F.Macbr. (1918:18)
Palo Alto thistle, Palo Alto lost thistle
Taxonomy & Nomenclature
Conservation Status
Extinct (Rejmánek, 2018; Smith, 2018; Humphreys et al., 2019; Knapp et al., 2020, 2021; Albani Rocchetti et al., 2022; POWO, 2024; Christenhusz & Govaerts, 2025; NatureServe, 2026)
Last record: 1901 (Rejmánek, 2018; Smith, 2018; Knapp et al., 2021; Christenhusz & Govaerts, 2025; NatureServe, 2026)
Distribution & Habitat
Palo Alto, Santa Clara County, California (northern), USA
Biology & Ecology
Hypodigm
Media
References
Original scientific description:
Macbride, J. F. (1918). [description of Cirsium praeteriens]. Contr. Gray Herb. 53: 19.
Other references:
Albani Rocchetti, Giulia, Carta, Angelino, Mondoni, Andrea, Godefroid, Sandrine, Davis, Charles C., Caneva, Giulia, Albrecht, Matthew A., Alvarado, Karla, Bijmoer, Roxali, Borosova, Renata, Bräuchler, Christian, Breman, Elinor, Briggs, Marie, Buord, Stephane, Cave, Lynette H., Da Silva, Nílber Gonçalves, Davey, Alexandra H., Davies, Rachael M., Dickie, John B., Fabillo, Melodina, Fleischmann, Andreas, Franks, Andrew, Hall, Geoffrey, Kantvilas, Gintaras, Klak, Cornelia, Liu, Udayangani, Medina, Leopoldo, Reinhammar, Lars Gunnar, Sebola, Ramagwai J., Schönberger, Ines, Sweeney, Patrick, Voglmayr, Hermann, White, Adam, Wieringa, Jan J., Zippel, Elke Zippel and Abeli, Thomas. (2022). Selecting the best candidates for resurrecting extinct-in-the-wild plants from herbaria. Nature Plants 8: 1385-1393. https://doi.org/10.1038/s41477-022-01296-7 [Supplementary Tables S1-S6]
Baldwin, B. B., Goldman, D. H., Keil, D. J., Patterson, R., Rosatti, T., and Wilken, D. (2012). The Jepson Manual, Vascular Plants of California second edition. Univ. California Press. 1568 pp.
Christenhusz, M. and Govaerts, R. (2023). Uitgestorven. Op plantenjacht rond de wereld: 1-511. Sterck & De Vreese.
Christenhusz, Maarten J. M. and Govaerts, Rafaël. (2025). Plant extinction in the Anthropocene. Botanical Journal of the Linnean Society 207(3): 183-196. https://doi.org/10.1093/botlinnean/boae045 [Appendix S1]
Humphreys, Aelys M., Govaerts, Rafaël, Ficinski, Sarah Z., Lughadha, Eimear Nic and Vorontsova, Maria S. (2019). Global dataset shows geography and life form predict modern plant extinction and rediscovery. Nature Ecology & Evolution 3: 1043-1047. https://doi.org/10.1038/s41559-019-0906-2 [Supplementary Dataset 1]
Kartesz, J. T. (1994). A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland
Kartesz, J. T. (1999). A synonymized checklist and atlas with biological attributes for the vascular flora of the United States, Canada, and Greenland. First edition. In: Kartesz, J.T., and C.A. Meacham. Synthesis of the North American Flora, Version 1.0. North Carolina Botanical Garden, Chapel Hill, N.C.
Keil, D. J. (2006). Cirsium, pp. 95-164. In: Flora of North America Editorial Committee, eds. 1993+, Flora of North America North of Mexico. 19+ vols. New York and Oxford. Vol. 19.
Knapp, Wesley M., Frances, Anne, Noss, Reed, Naczi, Robert F. C., Weakley, Alan, Gann, George D., Baldwin, Bruce G., Miller, James, McIntyre, Patrick, Mishler, Brent D., Moore, Gerry, Olmstead, Richard G., Strong, Anna, Gluesenkamp, Daniel and Kennedy, Kathryn. (2020). Regional records improve data quality in determining plant extinction rates. Nature Ecology & Evolution 4: 512-514. https://doi.org/10.1038/s41559-020-1146-1
Knapp, Wesley M., Frances, Anne, Noss, Reed, Naczi, Robert F. C., Weakley, Alan, Gann, George D., Baldwin, Bruce G., Miller, James, McIntyre, Patrick, Mishler, Brent D., Moore, Gerry, Olmstead, Richard G., Strong, Anna, Kennedy, Kathryn, Heidel, Bonnie and Gluesenkamp, Daniel. (2021). Vascular plant extinction in the continental United States and Canada. Conservation Biology 35(1): 360-368. https://doi.org/10.1111/cobi.13621 [Supporting Information (Appendix S1)]
Le Roux, Johannes J., Hui, C., Castillo, M. L., Iriondo, J. M., Keet, J.-H., Khapugin, A. A., Médail, F., Rejmánek, M., Theron, G. Yannelli, F. A. and Hirsch, H. (2019). Recent Anthropogenic Plant Extinctions Differ in Biodiversity Hotspots and Coldspots. Current Biology 29(17): 2912-2918.e2. https://doi.org/10.1016/j.cub.2019.07.063
Munz, P. A. (1968). Supplement to a California flora. Univ. California Press. Berkeley. 224 pp.
NatureServe. (2026). Cirsium praeteriens: Palo Alto Thistle. NatureServe Network Biodiversity Location Data accessed through NatureServe Explorer [web application]. NatureServe, Arlington, Virginia. Available at: https://explorer.natureserve.org/ [Accessed on 21 August 2026]
POWO. (2024). Plants of the World Online (online resource). Facilitated by the Royal Botanic Gardens, Kew, United Kingdom. Available at: https://powo.science.kew.org/ [Accessed 12 July 2024]
Rejmánek, Marcel. (2018). Vascular plant extinctions in California: A critical assessment. Diversity and Distributions 24(1): 129-136. https://doi.org/10.1111/ddi.12665
Roskov Y. et al. (eds.). (2018). Species 2000 & ITIS Catalogue of Life Naturalis, Leiden, the Netherlands.
Smith, James P. Jnr. (2018). California vascular plants: are some of them still out there? Botanical Studies 74: 1-4.
Thomas, J. H. (1961). Flora of the Santa Cruz Mountains of California: a manual of the vascular plants. Stanford, CA: Stanford University Press. 434 pp.
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