Филогенетические связи представителей рода Mesocestoides Vaillant, 1863 от микромаммалий востока России и Аляски

The article presents the data on structures of the nucleotide sequence fragments of the 12S ribosomal RNA gene (12S rRNA) for 19 tetrathyridia specimens of the genus Mesocestoides Vaillant, 1863 from representatives of 10 insectivore and rodent species from different regions of RussiaТs East and Alaska (USA). For the first time, the participation of three shrew species in the life cycle of Mesocestoides has been established. Nucleotide sequence fragments of the 12S rRNA gene have been analyzed phylogenetically. The researched tetrathyridia do not assumingly belong to any of the confirmed species of the genus; however, the identity of five of the 12S rRNA sequence fragments from micromammalian tetrathyridia and two nucleotide sequences of 12S rRNA from carnivorous mammals of Mongolia, placed in GenBank, has been established.