New contributions to the fauna of horseflies (Diptera, Tabanidae) in Azerbaijan, Nakhchivan

This study presents the first comprehensive investigation of the horsefly (Diptera: Tabanidae) fauna of the Nakhchivan Autonomous Republic, Azerbaijan, based on field surveys conducted between 2021 and 2025. A total of 451 specimens were collected and identified, comprising 37 species belonging to the subfamilies Tabaninae, Chrysopsinae and Pangoninae. Four species Tabanus nemoralis, T. obsolescens, Haematopota pallidula and H. pandazisi are recorded for the first time from Azerbaijan, while ten species are new records for Nakhchivan, raising the known Tabanidae fauna of the country to 90 species. Tabanus bifarius (20.39%) and T. bromius (17.52%) were the most frequently captured species, whereas Haematopota pandazisi, was rarely sampled, represented by only a single specimen. Ecological diversity analysis revealed the highest species richness in Julfa and Babek, while Ordubad (Goygol) and Ordubad (Pazmari) exhibited markedly reduced diversity, reflecting a clear altitudinal zonation of the fauna across the region. These findings substantially expand the known distribution and diversity of Tabanidae in Azerbaijan and provide baseline data for future ecological and veterinary research in Nakhchivan.