Ecological characteristics of 32 nonmarine ostracod taxa collected from 89 aquatic habitats of Erzincan (Turkey) during the summer of 2006 were evaluated. All of the species are new reports for the area, while Cypria sywulae Meisch, 2000 is a new record for the Turkish ostracod fauna. The first 2 axes of canonical correspondence analysis explain 74.1% of the variance between 15 species and 5 environmental variables. The influence of water temperature on species distribution was significantly higher (P = 0.02) than that of the other ecological factors. The most frequently occurring species were clustered into 3 main groups based on their ecological characteristics using unweighted pair group mean averages. Among the species, cosmopolitans showed a tendency to display wide ranges of tolerance values. Cypridopsis vidua (O. F. Muller, 1776) was the only species showing a significant (P = 0.03) negative correlation to habitat type (lentic versus lotic). Our results support the idea that once ecological characteristics of individual species are known, it is possible to use such knowledge in reconstructing past ecological conditions. However, application of this idea may not be limited to local/alpha species diversity. Indeed, our results suggest that studying gamma/regional diversity (Erzincan and environs) allows extending conclusions over a larger geographical scale and wider range of ecosystems.