Cytogenetic structure of Chironomus plumosus (L.) (Diptera, Chironomidae) population in regard to the trophic state of the Curonian Lagoon, Baltic Sea

It is shown that the cytogenetic structure of the Chironomus plumosus (L.) population in the Curonian Lagoon has not changed significantly over the last three decades. The existing cytogenetic structure supported not only population survival, but also its proliferation in new environmental conditions caused by an increase of the trophic status of the water body. The predominance of homozygotes pluB2.2 was marked in karyofund. Both the oxygen deficiency periodically occurring in the Curonian Lagoon and the fact that the population dwells at the periphery of the species areal in the Palearctic could be reasons for this phenomenon.