Edge Effect and the Influence of Biotic and Abiotic Factors on Calliphoridae and Mesembrinellidae (Insecta: Diptera) in Três Picos State Park, Brazil

The Atlantic Forest is a highly diverse biome that is under constant pressure due to human action, resulting in habitat fragmentation and intensifying edge effects, affecting biodiversity. The aim was to study the edge effect and influence of biotic and abiotic parameters on Calliphoridae and Mesembrinellidae communities in Três Picos State Park. Two traps baited using beef liver were placed at each site (n = 5) across 1000 m from the edge toward the interior of the forest, with vegetal characterization at each point. Collections occurred between June 2021 and May 2023, encompassing each season twice. The dipterans were identified taxonomically using a stereoscope microscope with the aid of taxonomic keys, totaling 5476 specimens. Dipteran abundance and species composition were primarily influenced by seasonal variation, while the distance from the forest edge or vegetation structure showed no effect. Abundance peaked during warmer periods, and temperature showed a positive effect on overall dipteran abundance. No species showed a strong association with specific seasons or distance along the edge-interior gradient. These results indicate that, in a relatively continuous and well-preserved forest remnant, edge effects do not lead to significant species loss, and climatic seasonality shapes patterns of dominance and abundance. Our findings highlight the ecological stability of the studied conservation unit and support the use of Calliphoridae and Mesembrinellidae as effective bioindicators. Understanding how dipteran assemblages respond to seasonal and edge-related gradients contributes to the development of cost-effective biomonitoring tools for tropical forest conservation.