Reappraisal and range extension of non-indigenous Mysidae (Crustacea, Mysida) in continental and coastal waters of eastern France - ABSTRACT

A survey of species belonging to the family Mysidae, conducted in June 2007 in fresh- to brackish waters of eastern France, revealed a recent range extension of the invasive Ponto-Caspian species Hemimysis anomala to the Moselle, Saône, and Rhône rivers. In the estuary of the Grand Rhône it reached for the first time the Mediterranean coast. The network of navigation canals in NE France was likely a key element of its north to south pathway starting from the Rhine River. Important range extensions were also noted for Limnomysis benedeni in this network and in the Moselle River. The euryhaline species Neomysis integer, endemic in coastal waters of the NE Atlantic, was found in the Rhône delta, thus confirming previous very rare records in the 1930–1950s from the Mediterranean coast of France. Invasion mechanisms and pathways, expansion potential, and establishment conditions of the species are discussed.