Variability of Karyofunds of Chironomus plumosus (Diptera, Chironomidae) from the Rybinsk Reservoir during the Period of Climate Warming

Abstract

This paper presents the results of an analysis of karyotypes of larvae of Chironomus plumosus L., 1758 from the Rybinsk Reservoir collected in 2016–2019. Fourteen sequences of discs of polytene chromosomes have been revealed in 367 individuals. The karyofund of the studied population has been enriched with 23 new genomic combinations and includes 136 combinations for 1013 individuals throughout the period of our observations (2013–2019). The frequency of occurrence of the “standard” genomic combination is 0.7%; the frequency of occurrence of pluA3 and pluA4 sequences, which are characteristic of the reservoir, has also increased. The frequency of occurrence of the pluE1.2 combination has significantly increased. There is a trend towards a decrease in intrapopulation cytogenetic distances. An analysis of differences in the frequency of occurrence of individual sequences throughout the observation period has been carried out.