Biogeography of the Daphnia O. F. Müller, 1785 (Branchiopoda: Anomopoda) in the North of Iran

The Daphnia distribution in Iran has been slightly studied and the information are very vague, although Daphnia is the oldest studied Cladoceran in the world. Here this is the first biogeographical assessment of the Daphnia in Iran. We collected the samples randomly from various stations of the Caspian and Urmia Lake Basins. Four Daphnia (Ctenodaphnia) and four Daphnia (Daphnia) were found in 29 different localities. We examined some ecological variables such as temperature, salinity, pH, altitude, latitude and longitude along with 19 bioclimatic variables for statistical analysis of factors affecting distribution. The average annual temperature, average temperature of the coldest quarter of the year and altitudes varied between the species, and thus were determined their bio-climatic requirements. The relationship between Daphnia distribution and the mean annual temperature and altitude were positive and with the average temperature of the coldest quarter of the year was negative. In general, temperature variations are considered as the only factors influencing the distribution of Daphnia and the variables associated with Precipitation are not affected.