Vistula barbel
The Vistula barbel is a disputed species of European freshwater fish in the cyprinid genus Barbus.
It is often included in B. cyclolepis. More recently, it has been hypothesized to be a natural hybrid that originated from a common barbel female mating with a Carpathian barbel male. Nevertheless, the populations do not seem to represent first-generation hybrids. It is recorded or suspected from Poland, Slovakia and Ukraine.