CHROMOSOMAL-POLYMORPHISM IN URAL AND SIBE RIAN POPULATIONS OF CAMPTOCHIRONOMUS-TENTANS

A standard photomap of polytene chromosomes of C. tentans is giyen. Th e chromosomal polymorphism in one laboratory and fifteen natural popul ations of C. tentans is described. Thirty one invert sequences and for ty four genotypic combinations of these sequences are detected. It is shown that most widespread sequences detected in Ural and Siberian pop ulations are identical with sequences described by Beermann (1952, 195 5) and Acton (1955, 1957) for European populations. Eight new rare inv ert sequences are found. Statistically significant differences of the frequencies of some sequences in different populations are determined. Predominant sequences were: ten A1 - in the Kazakh population, ten F2 - in the Altai population, ten C1 - in the laboratory population. New rare sequences are observed in Cheliabinsk and the Altai lakes pollut ed by radionuclides. The great difference in banding patterns between the studied American and Siberian populations of C. tentans is shown. We suggest that American C. tentans is a sibling species of Siberian a nd European C. tentans.