Epioblasma personata Say, 1829
Fine-rayed pearly mussel, Round snuffbox, Round combshell
Taxonomy & Nomenclature
Synonyms: Unio personatus Say, 1829; Dysnomia (Pilea) personata (Say, 1829); Dysnomia personata (Say, 1829); Epioblasma (Pilea) personatum (Say, 1829); Margarita (Unio) personatus (Say, 1829); Margaron (Unio) personatus (Say, 1829); Plagiola (Pilea) personata (Say, 1829); Plagiola personata (Say, 1829); Truncilla (Pilea) personata (Say, 1829); Unio pileus I. Lea, 1831; Margarita (Unio) pileus (I. Lea, 1831); Margaron (Unio) pileus (I. Lea, 1831); Unio capillaris I. Lea, 1834
Conservation Status
Extinct (Régnier et al., 2009; Cummings & Cordeiro, 2011b; NatureServe, 2014, 2025; Cowie et al., 2017; Graf & Cummings, 2021, 2025)
Last record: 1924 (Cummings & Cordeiro, 2011b)
IUCN RedList status: Extinct
No live specimen of the Fine-rayed pearly mussel was ever observed (Cummings & Cordeiro, 2011), and so its minimum extinction date cannot be inferred until radiocarbon dating of sub-fossil shells is done.
Distribution & Habitat
Illinois, Indiana, Kentucky, [Oklahoma?] & Ohio, USA
It may also have occurred in Oklahoma, but this may also have simply been an erroneous locality record (Mather & Tomer, 2006).
Biology & Ecology
Hypodigm
3 specimens are in the Illinois Natural History Survey mollusc [url=http://www.inhs.illinois.edu/animals_plants/mollusk/]collection[/url]:
INHS 1468
INHS 8357
INHS 20321
Media
References
Original scientific description:
Say T. (1829). Descriptions of some new terrestrial and fluviatile shells of North America. (cont.). The Disseminator of Useful Knowledge; containing hints to the youth of the U. States, from the School of Industry 2(20): 308-310.
Other references:
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Cummings, Kevin S. and Cordeiro, J. (2011b). Epioblasma personata. The IUCN Red List of Threatened Species 2011: e.T7879A12860921. https://dx.doi.org/10.2305/IUCN.UK.2011-2.RLTS.T7879A12860921.en. Accessed on 02 July 2022.
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