Characiform fishes (Teleosts, Ostariophysi): how many waves of immigration into Europe during the Cenozoic?

The occurrence of fossil characiforms in Europe was first observed more than forty years ago in the Lower Eocene of the Paris Basin. Since that time, they have been reported from the Maastrichtian of Romania and Southern France, then in the Oligocene of Provence, the Middle Miocene of Southwest France, the Upper Miocene of Portugal, and, more recently, in the basal Eocene of Belgium. Morphological comparison has shown that they belong to more or less strikingly different taxa. This supports the hypothesis that the fossil characiforms found in Europe reached this continent during several independent waves of immigration.