Parasite communities and genetic structure of non-native pumpkinseed,Lepomis gibbosus, in different Black Sea drainages of Ukraine

Abstract

In recent years, pumpkinseedLepomis gibbosus(Actinopterygii: Centrarchidae) have spread intensively to many parts of Europe, including Ukraine. In this study, we (1) assess intra-population genetic variability in five widely-spaced Ukrainian pumpkinseed populations and compare their population genetic structure with other European populations and (2) provide a comprehensive survey of pumpkinseed parasites across the region. Discriminant analysis of principal components and FSTanalyses based on microsatellites indicated that all five populations formed discrete clusters. Within Europe, Ukrainian populations were most closely associated with populations from the River Danube, suggesting that the Danube is the main source of all Ukrainian pumpkinseed populations. The parasite fauna comprised 15 taxa, most of which (92%) were native to North America (monogeneaOnchocleidus similisandO. dispar; myxozoanMyxobolus dechtiari). Parasites acquired in the species' new range occurred accidentally, with onlyTrichodinaciliates found relatively frequently and the eye flukesDiplostomum pseudospathaceumandTylodelphys clavataoccurring at higher prevalence. Absence of specific monogeneans in pumpkinseed from estuaries (Khadzhibey and Sukhyi Lymans) indicates low tolerance ofOnchocleidusspecies to salinity.