[Results of the study of the geographical variability of the parasite fauna and of the structure of component communities of the minnow parasite Phoxinus phoxinus (L.) 1. Basins of the Kama and Northern Dvina Rivers].

In the basin of the Kama River, in upper Vychegda River, and in tributaries of the upper Northern Dvina River, the parasite fauna of the minnow is monotonous and component communities of parasites are mature (balanced, according to Pugachev, 1999). They are completely formed in June.