Micranthemum micranthemoides Wettst. (1891:77)
Pearl weed, Nuttall’s mudflower, Nuttall's micranthemum
Taxonomy & Nomenclature
Synonyms: Herpestis micrantha Pursh in Fl. Amer. Sept. 2: 418 (1813); Hemianthus micranthemoides Nutt. in J. Acad. Nat. Sci. Philadelphia 1: 119 (1817); Herpestis micrantha Elliott in Sketch Bot. S. Carolina 2: 105 (1822), nom. illeg.; Micranthemum micrantha (Pursh) Alph.Wood in Class-book Bot.: 525 (1861); Micranthemum nuttallii A.Gray in Manual, ed. 5: 331 (1867); Globifera micranthemoides Kuntze in Revis. Gen. Pl. 2: 461 (1891); Hemianthus micranthus (Pursh) Pennell in Torreya 19: 150 (1919)
Conservation Status
Missing (NatureServe, 2026 [reviewed in 1995]) or Extinct (WCMC, 1992:222; Knapp et al., 2021; Abeli et al., 2022b) or Extinct in the Wild (Christenhusz & Govaerts, 2025; POWO, 2024)
Last (wild) record: 13 September 1941 (NatureServe, 2026 [global]); 1941 (Knapp et al., 2021 [global]; Christenhusz & Govaerts, 2025 [wild])
Distribution & Habitat
District of Columbia (=Washington, D.C.), Delaware, Maryland, New Jersey, New York, Pennsylvania & Virginia, USA
Biology & Ecology
Hypodigm
Media
References
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Abeli, Thomas, Sharrock, Suzanne and Albani Rocchetti, Giulia. (2022b). Out-of-date datasets hamper conservation of species close to extinction. Nature Plants 8: 1370-1373. https://doi.org/10.1038/s41477-022-01293-w
Christenhusz, Maarten J. M. and Govaerts, Rafaël. (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]
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