New information on the biology and distribution of Zerynthia polyxena (Denis et Schiffermüller, 1775) in Belarus

Abstract

New information on the distribution and dynamics of the number Southern Festoon – Zerynthia polyxena (Denis et Schiffermüller, 1775) in Belarus is provided. Currently, there are five isolated areas of the Belarusian fragment of the range in the country, localized in the valleys of the Dnieper, Sozh, and Pripyat Rivers. The water regime of the rivers is characterized by a strong spring flood, which in some years have the character of catastrophic floods and leads to flooding of the butterfly habitats. The warming of the climate, accompanied by frequent winter thaws, has led to a significant decrease in spring floods and their displacement to earlier dates. As a result, Southern Festoon has spread more widely in the South-East Belarus. The largest number of the species speciment was found in 2016-2020, which we associate with the period of weak spring floods on the rivers. Probably, during this period, the species actively explored new habitats in floodplain ecosystems and reached the latitude of Rechytsa City. In 2022 and 2023, there were observed extremely high floods in the South-East of Belarus. As a result of high floods, the number of Polyxena has fallen tenfold and the species has been preserved mainly on the most elevated terrain areas or at a considerable distance from rivers. In years with extreme spring floods, Polyxena does not fly out to the open floodplain and has no opportunity to settle.