Sedelnikovaea baicalensis, the Siberian-Central Asian lichen species, is recorded for the first time for Europe. Based on all the known localities, including those first-time reported from Baikal Siberia, the peculiarities of the ecology and distribution of this species are discussed, the map of its distribution is provided. It is concluded that the species was erroneously considered earlier as a Central Asian endemic. The center of the present range of this lichen is the steppes of Southern Siberia and Mongolia. Assumptions are made that S. baicalensis is relatively young (Paleogene-Neogene) species otherwise it would have a vast range extending beyond Asia, and also that the Yakut locations of this species indicate that in the Pleistocene its range was wider and covered a significant part of the Northeastern Siberia but later underwent regression. Based on the fact that in the mountains of Central Asia the species is found only in the upper mountain belts, it is proposed to characterize it as «cryo-arid xerophyte» in contrast to «arid xerophytes». A conclusion is made that the presence of extensive disjunctions of S. baicalensis range between the Southern Pre-Urals and the Altai-Sayan Mountains or the Mountains of Central Asia is unlikely; the lichen is most likely to occur in the Urals and most of Kazakhstan.
Trans-lithospheric diapirism explains the presence of ultra-high pressure rocks in the European Variscides
