Alasmidonta wrightiana (Walker, 1901)
Ochlockonee arcmussel
Taxonomy & Nomenclature
Synonyms: Strophitus wrightianus B. Walker, 1901 (basionym); Lampsilis wrightiana (B. Walker, 1901); Strophitus (Jugosus) wrightianus (B. Walker, 1901)
See Graf & Cummings (2025) for a more complete taxonomic history.
Conservation Status
Missing (NatureServe, 2025) or Extinct (Bogan, 2000b; Régnier et al., 2009; Cowie et al., 2017; Graf & Cummings, 2021, 2025)
Last record: 1931 (NatureServe, 2014, 2025)
IUCN RedList status: Extinct
Distribution & Habitat
Ochlockonee River, Florida, USA
Reports of this species from Georgia (Walker, 1901; Athearn, 1998) are likely in error (NatureServe, 2014).
Biology & Ecology
Hypodigm
Only known from 15 specimens.
Holotype: MZUM 74938
Media
References
Original scientific description:
Walker, B. (1901). A new species of Strophitus. The Nautilus 15(6): 65-66, plate 3.
Other references:
Athearn, H. D. (1998). Additional records and notes on the unionid fauna of the Gulf Drainage of Alabama, Georgia, and Florida. Occasional Papers on Mollusks, 5(76): 465-467.
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.
Bogan, A. E. (1993). Freshwater bivalve extinctions (Mollusca: Unionoida): A search for causes. American Zoologist 33: 599-609.
Bogan, A. E (2000a). Alasmidonta wrightiana. In: IUCN 2011. IUCN Red List of Threatened Species. Version 2011.1. (http://www.iucnredlist.org). Downloaded on 07 July 2011.
Bogan, A.E. (Mollusc Specialist Group). (2000b). Alasmidonta wrightiana. The IUCN Red List of Threatened Species 2000: e.T778A13078151. https://dx.doi.org/10.2305/IUCN.UK.2000.RLTS.T778A13078151.en. Accessed on 30 June 2022.
Burch, J. B. (1975). Freshwater Unionacean Clams (Mollusca: Pelecypoda) of North America. 204 pp.
Clarke, A. H. (1981). The tribe Alasmidontini (Unionidae: Anodontinae), Part I. Pegias, Alasmidonta, and Arcidens. Smithsonian Contributions to Zoology. No. 326. iii + 101 pp.
Clench, W. J. and Turner, R. D. (1956). Freshwater mollusks of Alabama, Georgia, and Florida from the Escambia to the Suwanee River. Bulletin of the Florida State Museum Biological Sciences, 1(3): 97-239.
Cowie, Robert H., Régnier, Claire, Fontaine, Benoît, and Bouchet, Philippe. (2017). Measuring the Sixth Extinction: what do mollusks tell us? The Nautilus 131(1): 3-41.
Frierson, L. S. (1927). A Classified and Annotated Check List of the North American Naiades. 111 pp.
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
Graf, Daniel L. and Cummings, Kevin S. (2025). The Freshwater Mussels (Unionoida) of the World (and other less consequential bivalves). MUSSEL Project Web Site, https://www.mussel-project.net/. Accessed 26 June 2025.
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. (1969a). Superfamilia Unionacea. Das Tierreich 88: x, 1-663. Walter de Gruyter & Co., Berlin.
Haas, F. (1969b). Superfamily Unionacea. Treatise on Invert. Paleo: N411-N470.
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
IUCN. (1990). 1990 IUCN Red List of Threatened Animals. Gland, Switzerland and Cambridge, UK.
Johnson, R. I. (1967). Additions to the Unionid fauna of the Gulf Drainage of Alabama, Georgia and Florida (Mollusca: Bivalvia). Breviora, 270: 1-21.
Johnson, R. I. (1970). The systematics and zoogeography of the Unionidae (Mollusca: Bivalvia) of the southern Atlantic Slope Region. Bulletin of the Museum of Comparative Zoology 140(6): 263-449.
MolluscaBase eds. (2025). MolluscaBase. Alasmidonta wrightiana (B. Walker, 1901). Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=857251 on 2025-06-27
NatureServe. (2014). NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://explorer.natureserve.org. (Accessed: January 27, 2015).
NatureServe. (2025). Alasmidonta wrightiana: Ochlockonee Arcmussel. NatureServe Network Biodiversity Location Data accessed through NatureServe Explorer [web application]. NatureServe, Arlington, Virginia. Available at: https://explorer.natureserve.org/ [Accessed 27 June 2025]
Pursifull, Sandra, Holcomb, Jordan, Rowe, Matthew, Williams, James D. and Wisniewski, Jason M. (2021). Status of Freshwater Mussels in the Ochlockonee River Basin of Georgia and Florida. Southeastern Naturalist 20(1): 1-19. https://doi.org/10.1656/058.020.0101
Régnier, Claire, Fontaine, Benoît and Bouchet, Philippe. (2009). Not Knowing, Not Recording, Not Listing: Numerous Unnoticed Mollusk Extinctions. Conservation Biology 23(5): 1214-1221. https://doi.org/10.1111/j.1523-1739.2009.01245.x [Appendix S1-S2]
Simpson, Charles Torrey. (1914). A descriptive catalogue of the naiades, or pearly fresh-water mussels. Parts I-III. Detroit, Michigan: Bryant Walker. 1540 pp.
Thiele, J. (1934). Handbuch der systematischen Weichtierkunde 3: 779-1022.
Turgeon, D. D., Bogan, A. E., Coan, E. V., Emerson, W. K., Lyons, W. G. et al. (1988). Common and Scientific Names of Aquatic Invertebrates from the United States and Canada: Mollusks. American Fisheries Society Special Publication (16). 277 pp.
Turgeon, D. D., Quinn, J. F., Jr., Bogan, A. E., Coan, E. V., Hochberg, F. G., Lyons, W. G., Mikkelsen, P. M., Neves, R. J., Roper, C. F. E., Rosenberg, G., Roth, B., Scheltema, A., Thompson, F. G., Vecchione, M. and Williams, J. D. (1998). Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks. 2nd Edition. American Fisheries Society Special Publication 26, Bethesda, Maryland: 526 pp.
Whelan, N. V., Johnson, N. A., Williams, A. S., Perkins, M. A., Beaver, C. E. and Mays, J. W. (2023). Hidden in the hills: phylogeny of the freshwater mussel genus Alasmidonta (Bivalvia: Unionidae) and description of a new species. Zoological Journal of the Linnean Society 198(2): 650-676. https://doi.org/10.1093/zoolinnean/zlac106
Williams, James D., Bogan, Arthur E., Butler, Robert S., Cummings, Kevin S., Garner, Jeffrey T., Harris, John L., Johnson, Nathan A. and Watters, G. Thomas. (2017). A revised list of the freshwater mussels (Mollusca: Bivalvia: Unionida) of the United States and Canada. Freshwater Mollusk Biology and Conservation 20: 33-58.
Williams, James D. and Butler, R. S. (1994). Class Bivalvia, Order Unionoida, freshwater bivalves, pp. 53-128, 740-742. In: Deyrup, M. and Franz, R. (eds.). Rare and Endangered Biota of Florida. Volume IV. Invertebrates. Gainesville, Florida: University Press of Florida. 798 pp.
Williams, James D., Butler, R. S., Warren, G. L. and Johnson, N. A. (2014). Freshwater Mussels of Florida. University of Alabama Press, Tuscaloosa. 498 pp.
Williams, James D., Butler, R. S. and Wisniewski, J. M. (2011). Annotated synonymy of the Recent freshwater mussel taxa of the families Margaritiferidae and Unionidae described from Florida and drainages contiguous with Alabama and Georgia. Bulletin of the Florida Museum of Natural History 51(1): 1-84.
Williams, James D., Warren, M. L., Jr., Cummings, K. S., Harris, J. L. and Neves, R. J. (1993). Conservation status of freshwater mussels of the United States and Canada. Fisheries 18(9): 6-22.
https://extinctanimals.proboards.com/thread/10350/alasmidonta-wrightiana-ochlockonee-arcmussel
<< Back to the Bivalvia (Mussels, Clams, Oysters etc.) database