[Molecular and cytogenetic approaches to species diagnostics, systematics, and phylogenetics]

Modern approaches to systematics and phylogenetics, based on statistical analysis of molecular data, allow to conduct diagnostics and objective delimitation of taxa, establish alliances, detect monophyletic groups, verify the naturalness of polytypic species, reveal cryptic evolution lines, retrace the history of nascency and dispersion of species and populations, and reconstruct phylogenies. Nevertheless, there are limitations on molecular data use due to impossibility of paleontological material examination. Chromosomal rearrangements combine the advantages of molecular and morphological characteristics with the unique patterns of their evolution. Conservative parts of genome may be synapomorphies of high-rank taxa while labile regions reliably mark evolutional events associated with speciation. New chromosomal rearrangements are being fixed rather quickly in homozygous state which allows to solve such problem of related species systematics as polymorphism of standard markers (especially molecular ones), often exceeding the level of inter-species differences. Thus, karyosystematics armed with such modern chromosome studying method as FISH, maintains and even enhances its importance as an instrument for solving taxonomic and phylogenetic problems.