Winter Activity of Fungus Gnats (Diptera: Mycetophilidae) in Critically-endangered Mediterranean Habitats in Bulgaria

Adult fungus gnats inhabit predominantly humid forest areas; however, they are sometimes found also in drier forest habitats, generally avoiding wetter environments. In European temperate climate, they are mainly active during the period from April to September. However, in the most south-western regions of Bulgaria where Mediterranean and Sub-Mediterranean habitats are found, it has been established that specific conditions during the winter might be a precondition for the extremely high abundance of fungus gnats in the area. Our study was conducted using tree and soil traps. A total of 28,557 specimens were collected during the winter months (November 2002, 2003, 2018; December 2002, 2003, 2018 and January 2003, 2019). Several species of the genera Phronia Winnertz, 1863, Coelosia Winnertz, 1863 and Boletina Staeger, 1840, were found to be dominant during that time, with Stigmatomeria crassicornis (Stannius, 1831) being reported for the first time for the fauna of Bulgaria.