Do reproductive modes and swimming ability influence occurrence of non-marine ostracod (crustacea) species among aquatic habitats?

Abstract

To gain a better understanding of the effect of reproductive modes and swimming ability on ostracod distribution, we visited 111 randomly selected aquatic sites in Kirsehir province. A total of 35 ostracods were newly reported for the area. The number of species with and without swimming setae was not statistically different, but numbers of sexual species was significantly lower than parthenogenetics. Species without setae did not show a significant difference between sexual and parthenogenetic forms. Numbers of species with (out) setae were not significant among different elevational ranges. Distribution of parthenogenetic species was common in all 11 habitat types when sexual species were only found from three different types located from 690 to ca. 1400 m of elevational ranges. Numbers of parthenogenetic species with or without setae did not show a difference among the ranges, but sexual species without setae exhibited wider distributional ranges (690-1289 m) than species with swimming setae (690-1089 m). Species' co-occurrence revealed two positive, five negative, and 44 random pairs of co-occurrences. Wards cluster analyses portrayed three main clustering groups. While group I includes parthenogenetic and sexual species, group II covers mostly parthenogenetic species with and without setae. Group III consists of species without setae. CCA results displayed three environmental variables (water temperature, pH and elevation) effective on species distribution. Species distributed in all elevational ranges tend to show lower optimum and wider ecological tolerances. Parthenogenetic species with swimming setae and with relatively higher tolerance ranges were dominant over sexual species. The present results suggest that swimming mode has a greater effect on species distribution among the habitats than reproductive modes.