Determination of the relationship betweenostracoda (Crustacea) carapace size andgeographic and ecological factors indifferent aquatic habitats of Mersin (Turkey)

In the present study, total of 117 different non-marine aquatic habitats were sampled from Mersin province during 03-09 October 2015. In total, 36 species and14 sub-fossils (valves or carapace) were detected from 66 of 117 sites. 34 of the 36 species found in here are new records for the province of Mersin. In addition, four ostracod taxa (Bradleycypris cf. obliqua, Cypretta cf. reticulata, Fabeaformiscandona cf. wegelini, Hemicypris cf. largereticulata) were new record for the Turkish Ostracoda fauna. Water and sediment samples were analyzed to show the relationship between distribution of ostracod species and their valve size at different elevational ranges. Valve length of 1990 individuals which found three or more than three times were measured. The first two axes of the Canonical Corresponding Analysis (CCA) revealed 72.6% of the relationship between 12 taxa and five ecological variables. Among the variables, water temperature (P <0.05) and pH were the most effective variable whereas elevation, salinity and dissolved oxygen were less effective on the taxa. According to C2 analysis, two species Ilyocypris inermis and Potamocypris fallax showed the lowest and highest optimum values for elevation, respectively. While Psychrodromus fontinalis had a maximum tolerance for elevation, Limnocthere inopinata showed a minimum tolerance. There was a significant difference between the length of right and left valves of the individuals (P<0.05, N = 1990). In contrast, some individuals of species displayed no significant difference when some species showed variabilities among elevational ranges. Aditionally, the species P. fontinalis showed no significant result related to elevation (N=191, t=1.45, P> 0.05 ) for all the individuals wheras Ilyocypris bradyi for all the individual of this species had showed significant result (N=308, t=4.24, P < 0.001) was observed. It is clear that there is a change in valve lengths as the elevation increases, but more sampling and more measurements are required to talk about the relationship between elevation and valve length.