Zonal features of the geographic distribution of chromosomal inversions in the populations of An. messae at the south of the Russian Plain were examined. The An. messae was identified based on morphological characters and cytogenetically. The chromosomal inversions identified in populations of An. messae comprised XL1, XL4, 2R1, 3R1, and 3L1. Inversion XL4 was endemic and found with low frequency (2%) in Penza oblast and Moscow oblast. Based on the population karyotype structure similarity, on the territory of Russian Plain, three zones (southwestern, southeastern, and central) were identified. Central zone was characterized by higher levels of inversion polymorphism in all chromosomes, except arm 3L. In the two southern zones, high frequency of the XL0 inversion, along with complete absence of homo- and heterozygotes for the 2R1 inversion, and high proportion of the individuals with inversion 3L1 was observed. Specific feature of southeastern zone was the increased frequency ofhetero- and homozygotes for the 3R1 and 3L1 inversions. Zonal differences reflected adaptive character ofchromosomal polymorphism and pointed to hierarchic organization of the species population structure.