Inter-primer Binding Site Markers (iPBS) are Used to Describe the Genetic Diversity of Populations of the Black-striped Pipefish Syngnathus abaster Risso, 1827 (Actinopterygii: Syngnathidae) in their Natural and Expansion Ranges in Ukraine

he black-striped pipefish (Syngnathus abaster) is an Atlanto-Mediterranean marine and estuarine fish species which recently expanded its range into freshwaters. iPBS genetic markers analysis revealed the population divergence of this fish species from different localities in Ukraine. In the course of molecular genetic analysis using four inter-primer binding site (iPBS) primers, 82 amplification fragments were detected. The difference between populations depends on the frequency of a particular allele allows us to separate the population from the Tylihul Estuary and all freshwater ones. The samples from the Dnipro River basin (Stuhna River and Dnipro Reservoir) related to different subclusters, which may indicate that the introduction of the pipefish into the Dnipro basin could have occurred several times and in different ways: 1. Natural range expansion; 2. Artificial acclimatisation; 3. Introduction with river transport. The differences in allele frequencies suggest the existence of populations with different origins in the Dnipro River, which can be explained by the introduction of this species from the delta areas of the Danube and Dniester (population from the Stuhna River) and self-settlement upstream of the Dnipro River (population from the Dnipro Reservoir).