Цитогенетическая характеристика видов рода Chironomus группы ‘‘plumosus’’ (Diptera, Chironomidae) природно-территориальных комплексов Уральского региона

Abstract

The polytene chromosomes of the cells of the salivary glands of the larvae of Ch. plumosus L. 1758, Ch. entis Shobanov 1989, Ch. borokensis Kerkis et al. 1988 and Ch. curabilis Beljanina et al. 1990 from 20 reservoirs of six natural-territorial complexes of the Ural region were studied. On the basis of a cytotaxonomic study, it was established that natural complexes differ from each other in the species composition of the “plumosus” group, the ratio (in %) between species and, certain parameters of cytogenetic variability of Ch. plumosus, Ch. entis and Ch. borokensis. Comparative analysis revealed differences between groups of natural complexes. A significantly lower frequency of occurrence of sequence of chromosome disks pluA1.2 was found within the Ural plain-mountainous country (Western foothill and Middle Ural low-mountain regions) compared with natural complexes on the eastern slopes of the Southern Urals and the West Siberian Plain at the junction with the Ural mountain range. Populations of Ch. plumosus of the Ural plain-mountain country have lower cytogenetic distances between themselves compared to populations of Ch. plumosus on the eastern slopes of the Southern Urals and the West Siberian Plain at the junction with the Ural Mountain Range. With respect to Ch. entis, these territories differ from each other in the absence of sequence of chromosome disks entА1.2 within the Ural plain-mountain country. According to cytogenetic distances, the populations of Ch. entis on the eastern slopes of the Southern Urals and the West Siberian Plain country at the junction with the Ural Mountain Range differ more from the population of Ch. entis of the Ural plain-mountain country than among themselves. In the north-south direction, it is necessary to indicate a significantly lower frequency of occurrence of sequence of chromosome disks borB1.2 within the Ural plain-mountain country (Eastern Podgorny region) relative to a natural complex with a more southern location within the West Siberian Plain country (Tura Plain region). For Ch. borokensis the interpopulation cytogenetic distances were calculated for the first time (0.0128±0.0017). Differences in this indicator between the natural complexes of the Ural region have not been established.