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    Distribution of Sexual and Asexual Ostracoda (Crustacea) from Different Altitudinal Ranges in the Ordu Region of Turkey: Testing the Rapoport Rule
    (Mary Ann Liebert, Inc, 2012) Kulkoyluoglu, Okan; Sari, Necmettin; Akdemir, Derya; Yavuzatmaca, Mehmet; Altinbag, Ceren
    Kulkoyluoglu, Okan, Necmettin Sari, Derya Akdemir, Mehmet Yavuzatmaca, Ceren Altinbag.. Distribution of sexual and asexual ostracoda (crustacean) from different altitudinal ranges in the Ordu region of Turkey: Testing the Rapoport Rule. High Alt. Med. Biol. 13: 126-137.-We evaluated Rapoport's rule which states a negative correlation between species richness and altitude. To understand the relationship between altitude and reproductive modes (a/sexual) of non-marine ostracods, 166 aquatic bodies in Ordu region, Turkey were randomly sampled from July 11 to July 16, 2010. Atotal of 26 species of ostracods were found from 133 out of 166 sites. Except for one species (Heterocypris incongruens), the other 25 species were new reports for the region. Candona improvisa was also a new report for Turkish ostracod fauna. Three species (Psychrodromus olivaceus, H. incongruens, and C. neglecta) occurred most frequently as 43, 46, and 76 times, respectively. Canonical correspondence analyses exhibited two variables [Habitat type (p = 0.014; F = 2.171) and water temperature (p = 0.018; F = 2.248)] as having the most effect on species. Correlation of species' reproductive modes to those of environmental variables measured was not significant. UPGMA dendrogram displayed 15 most frequently occurring species into four clusters where most species (11) were asexual. Although a small group (asexual species without swimming setae) showed a tendency to habitat type and electrical conductivity, such variables are believed to play secondary role on species distribution. Highest species diversity (13 species) was observed at the range of 1200 and 1400m (a.s.l.), where numbers of stations sampled was not the highest (22). Numbers of asexual species (19) were higher than the sexual (11) but there were no significant differences (p > 0.05) between the frequencies of their occurrences at different altitudinal ranges. Accordingly, our findings do not support the Rapoport Rule. Results yield that reproductive modes of species (sexual and asexual) was not directly correlated to altitude or any environmental variables measured during this study. A better explanation of ostracod diversity appears to be suitability of habitats.
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    Meteorological Forcing Shapes Seasonal Surface Zooplankton Dynamics in Lake Karamurat, a Small Tectonic Lake in Türkiye
    (Mdpi, 2026) Gurbuzer, Pinar; Kulkoyluoglu, Okan; Altindag, Ahmet
    In temperate freshwater ecosystems, zooplankton play a crucial role in the pelagic food web and act as sensitive indicators of environmental change. They respond to shifts in water temperature, hydrodynamic mixing, and short-term meteorological events. This study investigated the epilimnetic zooplankton fauna of Lake Karamurat (Bolu, T & uuml;rkiye), a small tectonic temperate lake, with a specific focus on the influence of rainfall events and wind speed on community structure. The samples were taken seasonally and horizontally using a plankton net (55 mu m mesh size) and were analyzed alongside in situ physico-chemical measurements and meteorological data. In total, 74 zooplankton taxa were identified, comprising 54 rotifer species and 20 crustacean species (16 Cladocera and 4 Copepoda). Testudinella greeni was recorded for the first time in T & uuml;rkiye, representing a new addition to the Turkish Rotifera fauna. Multivariate analyses revealed that electrical conductivity, water temperature, dissolved oxygen, precipitation, and wind speed were key drivers shaping community composition. The findings suggest that wind-driven surface mixing and episodic rainfall events enhanced vertical redistribution, leading to dominance of rotifers and small-bodied cladocerans in the epilimnion. These findings underscore the critical role of sampling strategy in shallow lakes under dynamic conditions and provide new faunistic insights into the zooplankton diversity of Anatolian lakes.