Institute of Marine Biology, National Academy of Science of Ukraine, Pushkinska St., 37, Odesa, 65048, Ukraine.
Odesa I. I. Mechnikov National University, Dvoryanska St., 2, Odesa, 65002, Ukraine.
Parasitol Res. 2024 Mar 6;123(3):154. doi: 10.1007/s00436-024-08174-5.
The big-scale sand smelt (Atherina boyeri) is an Atlanto-Mediterranean amphidromous fish species found within the Black Sea. Here, we assess differences in the parasite fauna of big-scale sand smelt populations from their natural range in the northwestern Black Sea and from their expansion range in the Lower and Middle River Dnipro. In addition, we undertook a microsatellite analysis to assess the genetic similarity of fish from the different locations. We found that the parasite community of fish in their natural range was wider than that from their expansion range. While the Gulf of Odesa was most distant from all other localities by parasite community composition and the Dnipro Reservoir was characterised by an absence of parasites (newest and most distant expansion locality), only fish from the Danube Delta showed a significant genetic difference. Our results suggest that the parasite community of big-scale sand smelt is primarily influenced by environmental factors, such as habitat type, water salinity and/or prey composition. Both microsatellite analysis and parasite community species composition (e.g. the presence of the marine Telosentis exiguus in the Kakhovka Reservoir and freshwater Raphidascaris sp. in the Gulf of Odesa) confirmed that populations in the River Dnipro reservoirs had, at some time, been connected with native marine populations, thus also confirming the species' amphidromous nature.
大鳞沙瑙鱼（Atherina boyeri）是一种分布于黑海的大西洋-地中海洄游鱼类。在这里，我们评估了大鳞沙瑙鱼自然分布区（黑海西北部）和扩展分布区（下第聂伯河和中第聂伯河）种群的寄生虫区系差异。此外，我们还进行了微卫星分析，以评估不同地点鱼类的遗传相似性。我们发现，自然分布区鱼类的寄生虫群落比扩展分布区鱼类的寄生虫群落更广泛。奥德萨湾与其他所有地点的寄生虫群落组成差异最大，而第聂伯水库则没有寄生虫（最新且最遥远的扩展分布区），只有多瑙河三角洲的鱼类表现出显著的遗传差异。我们的研究结果表明，大鳞沙瑙鱼的寄生虫群落主要受环境因素的影响，如栖息地类型、水的盐度和/或猎物组成。微卫星分析和寄生虫群落物种组成（例如，在卡霍夫卡水库中存在海洋 Telosentis exiguus 和在奥德萨湾中存在淡水 Raphidascaris sp.）都证实，第聂伯河水库中的鱼类种群曾经与本地海洋种群有联系，这也证实了该物种的洄游性质。
