Eskişehir (Türkiye) bölgesindeki ostrakoda (Crustacea) türlerinin birlikte bulunma durumlarının ve ekolojik karakterlerinin belirlenmesi

This study aimed to understand co-occurrence patterns and ecological characteristics of ostracod species in Eskişehir province. A total of 118 sampling sites were visited and 36 ostracod species were collected from the area during 11- 17 July 2020. Twenty four of 36 species were new reports for the province. Including the previously known 20 species, numbers of ostracods are elevated to 44 species. A new species, Eucypris dorlionensis, was found in the area. The most effective ecological variables on the species occurrences were determined as elevation, nitrite, and pH from the Canonical Correspondence Analysis. Species cooccurrence showed different patterns based on habitat types in the area. Accordingly, Ilyocypris bradyi co-occurred with Herpetocypris intermedia and Prionocypris zenkeri in the all-sampling sites. Heterocypris salina and I. bradyi were generally found together in the lentic waters while P. zenkeri was found with I. bradyi in the lotic habitats. According to C2 analysis results, some species have different tolerance for ecological variables both in the lentic and lotic habitats. Indicator species analysis suggested that Heterocypris incongruens seems to prefer a wide range of artificial and lentic habitats when Ilyocypris inermis preferred lotic and natural habitats. We determined sink and source habitats based on the numbers of species per site. Distribution of ostracod species in the province was modeled with Adespatial analysis. Accordingly, 10 groups were determined in the distribution model that was created based on the distance and species richness between the sampling sites. Results suggested that cosmopolitan species with similar preferences tend to co-occur in a variety of habitats. KEYWORDS: Ostracod, Diversity, Co-occurrence, Sink and Source Habitats, Distribution