Biological features and distribution of nectarophage Timia (Empyelocera) abstersa Loew (Diptera, Ulidiidae)

The distribution and spatial structure of the range of Timia abstersa (Ulidiidae) were analyzed for the first time. The map of this species distribution is based on the materials of the collection of the Zoological Institute of the Russian Academy of Sciences. It served as the basis for the analysis of the zonal landscape conditions of the distribution of the adult flies of T. abstersa and the cultivation of alfalfa – its main fodder plant. The nectarophagy of T. abstersa flies on alfalfa was first established on the basis of our laboratory and field studies in alfalfa crops in the forest-steppe of the Samara Region and according to literary data on the fodder nutrition of adult flies of this species in the southwestern part of Iran. The distribution of T. abstersa in forest-steppes, typical and dry steppes in lowland, foothill and on mountain plateaus from 28° to 92° east longitude and from 29° to 53° north latitude in the temperate and subtropical zones of Eurasia was noted. Two mountain centers of its formation have been identified in the area of T. abstersa: Transcaucasian-North Iranian and Central Asian. From the Transcaucasian-North Iranian mountain center, this species spread to flat landscapes in the north and northeast direction to Europe, western and northern Kazakhstan, Western Siberia, and from the Central Asian mountain center – in the east: along the foothills and mountains of southern Kazakhstan, northern China to Western Mongolia. The formation of T. abstersa centers is due to the greatest diversity of perennial wild alfalfa species in them, and the expansion of the range of T. abstersa is due to the increase in the territories of widespread cultivation of this crop.