Dataset on the Biodiversity and Seasonal Dynamics of Horseflies (Tabanidae, Diptera) in Some Regions of European Russia

The regional fauna of many Diptera groups is insufficiently studied. Tabanidae are the largest representatives of blood-sucking Diptera. A description of a dataset on the biodiversity of horseflies (Tabanidae) is presented, which includes information obtained by the authors and their colleagues in 2001, 2007–2009, and 2012–2025. The information was received from 14 regions of European Russia. A total of 5740 specimens were processed. In total, samples were obtained from 159 localities. Each record includes information about the species, time and place of collection, the collectors and determiners, as well as the administrative affiliation of the locality, making the dataset suitable for faunistic, biogeographical, and ecological studies. In total, 35 species were reliably identified. The most studied was the Republic of Mordovia, from which 33 species of Tabanidae became known. In turn, 12 species are included in the dataset from the Vladimir Region, and 10 species are included in the dataset from the Ryazan Region. Five species (Chrysops caecutiens, Chrysops viduatus, Haematopota pluvialis, Hybomitra bimaculata, Hybomitra muehlfeldi) were represented in the dataset in the largest number, and they accounted for 61.5% of the total specimens. The dataset also includes one specimen each of five species: Atylotus plebeius, Chrysops nigripes, Chrysops sepulcralis, Hybomitra borealis, and Hybomitra kaurii. Tabanidae activity begins in the first ten days of May and ends in the second ten-day period of September. The maximum species richness was observed in the third ten-day period of June and the first ten days of July, with 24 species recorded in each of these periods. Meanwhile, the maximum value of the Shannon index (2.52) and the minimum value of the Berger–Parker index (0.16) are observed in the first ten days of July. The dataset can be used as a basis for further study of the diversity and distribution of Tabanidae in European Russia.