The Freshwater Mussels (Unionoida) of the World (and other less consequential bivalves)
FM(U)otW(aolcb) is the web version of the MUSSEL Project Database. Follow the links to browse the data or use the custom Google search field. Either way, you win!
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nominal species Unio carbonarius Goldfuss, 1837
Goldfuss, 1837, Petrefacta Germaniae 2: 145, pl. 131, fig. 19.
(homonym of Unio carbonarius Lea, 1838)