EN
Fifteen new localities of the Ukrainian brook lamprey, Lampetra (Eudontomyzon) mariae, were found within 2008–2010. The majority of them are located in the Nida River drainage. Additionally, the occurrence of that species in the Strwiąż River, a tributary of the Dniester, was confirmed. The cluster analysis performed suggests, that L. mariae exhibits strong affinity to the stone loach, Barbatula barbatula, and the Eurasian minnow, Phoxinus phoxinus. We believe that the distribution of L. mariae on the territory of Poland seems to be strongly underestimated.