Ostracoda (Crustacea) species composition and environmental correlates in different aquatic habitats of the Zonguldak and Bartın regions (Turkey)

Abstract

In order to compare the ostracod species composition of the Zonguldak and Bartın regions of Turkey, samples were collectedfrom 105 aquatic sites with 7 different habitats during June 2013. Thirteen and 18 species were identified from Bartın and Zonguldak,respectively. While all of the species are new reports for Bartın, 11 species are new for Zonguldak. Twenty-two species were commonin both regions, with 40.9% similarities. Species abundance (49.2 individuals/site) was found to be greater in Zonguldak than in Bartın(33 individuals/site), but the number of species per sampling site was higher in Bartın (0.48 spp./site) than in Zonguldak (0.42 spp./site).Increasing the numbers of sampling sites did not increase the numbers of species. Among the habitat types, the numbers of species persite was the lowest in troughs (0.35 spp./site). Canonical correspondence analyses explained 78.3% of the correlation with relatively lowvariance (9.8%) between the 15 most common species and 4 environmental variables in the regions, where water temperature (F = 3.216;P = 0.002) and electrical conductivity (F = 2.525; P = 0.018) displayed strong correlation with the species. However, water temperatureper se did not show a significant effect on the numbers of species (P > 0.05). Cosmopolitan species showed relatively high tolerance andoptimum values to different environmental variables.