Genetic Determination of the Origin of Hemimysis anomala in the Laurentian Great Lakes

The most recent Ponto-Caspian species to invade the Laurentian Great Lakes is the crustacean Hemimysis anomala, c 2006.  A 549 bp fragment of the  mitochondrial cytochrome oxidase I gene from populations of H. anomala throughout the Great lakes was analyzed to determine if established populations in Lakes Ontario, Erie, Huron, Michigan and the St. Lawrence River share the same lineage.  Two different haplotypes, A1 and B1, were observed for H. anomala from Lakes Ontario, Erie, Huron, and the St. Lawrence River.  Previously published data from Lake Michigan indicated the presence of only the A1 haplotype and identified the Danube River as the source region.   Our results identify four regions as potential source populations for the invasion of H. anomala into the Great Lakes: Germany’s Lake Schwerin, the Mittellandkanal and the Lower Rhine, and the Danube River.  Our results show that multiple introductions of H. anomala into the Great Lakes from separate populations originating in Germany and the Ponto-Caspian region may have occurred.