Genetic diversity in Lampsilis siliquoidea across Lake Erie's tributaries

Application of genetic markers to identify population structure and connectivity across species distributions has only recently been applied to freshwater mussels.  Most published work focuses on variation in critically threatened or endangered species.  Across the Lake Erie watershed, the fat mucket, Lampsilis siliquoidea, inhabits most tributaries and is considered common.  Nonetheless, populations within small rivers may not be large and each is isolated from neighboring watersheds. A 600 bp section of the CO1 gene from both the female and male inherited mitochondria was sequenced from individuals collected from Lake Erie tributaries, the upper Mississippi watershed and the Ohio River watershed, and these were compared to a sibling species, L. radiata, from Maine. Several haplotype groups that predated colonization of Lake Erie occur in multiple tributaries, and these forge historical links to both the upper Mississippi and to the upper Ohio River faunas. Tributary specific haplotypes also highlight isolation of some populations. While all female-inherited mitochondria linked the Lake Erie species to L. siliquoidea, three individuals from eastern Ohio tributaries possessed male-inherited mitochondria of L. radiata origin. Therefore, even recent faunas, like those in the Great Lakes, may contain genetically unique forms even where no mussel species is endemic to the region.