Detection of biodiversity local centers and gradients of change of Dolichopodidae (Diptera) in East Asia

The dolichopodid fauna of continental Chinese and Russian regions belonging to the East Palaearctic have been selected for a comparative diversity investigation. We gathered information about 654 species of long-legged flies in the studied areas. Regarding the total species number, Primorsky Kray and Republic of Sakha in Russia, Henan and Shaanxi in China, as well as Mongolia are the top five regions, each with more than 100 species known. Cluster analysis of the dolichopodid genera composition allows us to divide all studied territories into two groups: Group A is mixed, since it includes both the Russian regions and the Chinese provinces; Group B includes only Russian regions. Generally, the mathematical analysis of the dolichopodid species supports the uniqueness of Primorsky Kray as the biodiversity center in East Asian Palaearctic. A decrease in the number of known species and biodiversity indices is observed northward, southward and westward of Primorsky Kray. One more possible center is located closely to the Oriental provinces of China (Henan and Shaanxi provinces).