Epioblasma flexuosa (Rafinesque, 1820)
Arcuate pearly mussel, Leafshell, Northern leafshell
Taxonomy & Nomenclature
Synonyms: Obliquaria (Quadrula) flexuosa Rafinesque, 1820 (basionym); Obliquaria (Quadrula) flexuosa Rafinesque, 1820; Obliquaria (Quadrula) flexuosa var. bullata Rafinesque, 1820; Unio foliatus Hildreth, 1828; Unio flexuosus Rafinesque, 1820; Margarita (Unio) foliatus Hildreth, 1828; Margaron (Unio) foliatus Hildreth, 1828; Dysnomia flexuosa Rafinesque, 1820; Truncilla (Dysnomia) foliata Hildreth, 1828; Dysnomia (Dysnomia) flexuosa Rafinesque, 1820; Plagiola (Epioblasma) flexuosa Rafinesque, 1820
See Graf & Cummings (2025) for a more complete taxonomic history.
Conservation Status
Extinct (Stansberry, 1976; Bogan, 2000b; Régnier et al., 2009; NatureServe, 2014, 2025; Cowie et al., 2017; Graf & Cummings, 2021, 2025)
Last record: 19th century? (Bogan, 2000b); 1900 (Stansberry, 1976 fide NatureServe, 2014, 2025)
IUCN RedList status: Extinct
Distribution & Habitat
Alabama, Illinois, Indiana, Kentucky, Ohio and Tennessee, USA
Type locality: Kentucky River
Biology & Ecology
Hypodigm
Lectotype: ANSP 20249 (male, selected by Johnson & Baker, 1973:155)
Other specimens:
ANSP 56571 (female, type of Unio foliatus Hildreth, 1828)
INHS 1747
INHS 4379
INHS 4751
INHS 4779
INHS 5922
INHS 6034
INHS 6726
INHS 23078
INHS 24132
INHS 25209
INHS 28711
INHS 28955
INHS 32709
INHS 41696
INHS 41708
Source:
http://ellipse.inhs.uiuc.edu:591/INHSCollections/FMPro
Media
References
Original scientific description:
Rafinesque C.S. (1820). Monographie des coquilles bivalves et fluviatiles de la Rivière Ohio, contenant douze genres et soixante-huit espéces. Annales Générales des Sciences Physiques 5(5): 287-322, pls 80-82.
Other references:
Agassiz, L. (1852). Ueber die Gattungen unter den Nord Amerikanischen Najaden. Archiv für Naturgeschichte 18(1): 41-52.
Baillie, J. and Groombridge, B. (eds). (1996). 1996 IUCN Red List of Threatened Animals. pp. 378. International Union for Conservation of Nature, Gland, Switzerland and Cambridge, UK.
Baker, F. C. (1928). The fresh water Mollusca of Wisconsin. Part II. Pelecypoda. Bulletin of the Wisconsin Geological and Natural History Survey 70(2): vi-495 + 76 plates.
Bogan, Arthur E. (1993). Freshwater bivalve extinctions (Mollusca: Unionoida): A search for causes. American Zoologist 33(6): 599-609. https://doi.org/10.1093/icb/33.6.599
Bogan, Arthur E. (2000a). Epioblasma flexuosa. In: IUCN 2011. IUCN Red List of Threatened Species. Version 2011.2. (http://www.iucnredlist.org). Downloaded on 22 April 2012.
Bogan, Arthur E. (Mollusc Specialist Group). (2000b). Epioblasma flexuosa. The IUCN Red List of Threatened Species 2000: e.T7868A12859429. https://dx.doi.org/10.2305/IUCN.UK.2000.RLTS.T7868A12859429.en. Accessed on 19 June 2022.
Burch, J. B. (1975). Freshwater unionacean clams (Mollusca: Pelecypoda) of North America. Malacological Publications: Hamburg, Michigan. 204 pp.
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Graf, Daniel L. and Cummings, Kevin S. (2021). A ‘big data’ approach to global freshwater mussel diversity (Bivalvia: Unionoida), with an updated checklist of genera and species. Journal of Molluscan Studies 87(1): eyaa034 (36 pp.). https://doi.org/10.1093/mollus/eyaa034
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Groombridge, B. (ed.). (1994). 1994 IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland and Cambridge, UK.
Haag, Wendell R. (2009). Past and future patterns of freshwater mussel extinctions in North America during the Holocene, pp. 107-128. In: Turvey, Samuel T. (ed.). Holocene Extinctions. Oxford, UK & New York, USA: Oxford University Press. xii + 352 pp.
Haas, F. (1930). Über nord-und mittelamerikanische Najaden. Senckenbergiana 12(6): 317-330.
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Hildreth, S. P. (1828). Observations on, and descriptions of the shells found in the waters of the Muskingum River, Little Muskingum, and Duck Creek, in the vicinity of Marietta, Ohio. American Journal of Science and Arts 14(2): 276–291. [description of E. foliatus, a junior synonym of E. flexuosa]
Hilton-Taylor, Craig. (2000). 2000 IUCN Red List of Threatened Species. IUCN, Gland, Switzerland and Cambridge, UK.
Hopper, G. W., Bucholz, J. R., DuBose, T. P., Fogelman, K. J., Keogh, S. M. et al. (2023). A trait dataset for freshwater mussels of the United States of America. Scientific Data 10: 745 (pp. 1-15). https://doi.org/10.1038/s41597-023-02635-9
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http://www.natureserve.org/explorer/servlet/NatureServe?searchName=Epioblasma+flexuosa+
https://extinctanimals.proboards.com/thread/10363/epioblasma-flexuosa-arcuate-pearly-mussel
https://www.extinction.photo/species/arcuate-pearly-mussel/
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