An electrophoretic survey of isozyme systems of some populations in 4 Central European Cinclidotus species shows that the species are genetically clearly separated. Nine of sixteen tested enzyme systems were scoreable. Qualitative differences between species are detected in five of the scored enzyme systems. The theory of a hybrid origin of Cinclidotus danubiens is discussed but dismissed.
Aquatic moss, Cinclidotus, variability of species, isozyme, Central Europe