Expanding the faunal knowledge of Azerbaijan: new Diptera records from randomized surveys

Abstract

The Caucasus is recognized as a global biodiversity hotspot; however, the diversity of many insect groups, including Diptera, remains insufficiently documented, particularly within protected areas. In this study, we present new faunistic data on Diptera from Azerbaijan based on material collected between 2011 and 2025 across a wide range of habitats and elevations, including several national parks and nature reserves. A total of 123 species/taxa belonging to 21 families were recorded, of which 85 species are reported from Azerbaijan for the first time, substantially expanding the known distribution of numerous taxa in the Caucasus region. New country records were identified across multiple dipteran families, highlighting the high yet still underestimated diversity of flies in the studied area. A considerable portion of the material originated from protected areas, emphasizing their importance as reservoirs of previously undocumented invertebrate diversity. Our results demonstrate that even non-targeted and opportunistic sampling can yield significant faunistic discoveries in biodiversity-rich but poorly explored regions. The study further underlines the need to integrate Diptera and other invertebrates more explicitly into biodiversity assessments and research programs within protected areas of the Caucasus.