A new oribatid mite species of the family Thyrisomidae, Pantelozetes unitjumeniensis sp. nov., is described from the taiga forest at the eastern bank of lake Baikal (Siberia, Russia). The new species is morphologically most similar to Pantelozetes bayartogtokhi Ermilov, Salavatulin & Tolstikov, 2014 nom. nov., however, it differs from the latter by the larger body size, presence of body ornamentation and well developed costulae. Pantelozetes mongolicus (Balogh & Mahunka, 1965) is recorded for the first time in Russia. A new generic diagnosis of Pantelozetes is presented. A new species name is proposed: Pantelozetes bayartogtokhi (=Montizetes serratus Bayartogtokh, 2003, preoccupied by Wang & Cui 1996).