Species richness and regions of high diversity of terrestrial vertebrates in Russia

A revision of the species richness of four vertebrate classes (mammals, birds, reptiles, and amphibians) within the territory of Russia was conducted. The regional-level biome was adopted as the territorial unit. An increase in species richness towards the south is characteristic for all classes, with specific differences for each class reflected on our plotted maps. The zones of high diversity partially overlap; however, the biomes with the maximum values do not coincide. For mammals, these are the Black Sea-Ciscaucasian (113 species) and the Zavolzhsky-Kulunda (114 species) steppe biomes. For birds, they are the Sayan-Southern Transbaikal (262 species) and the Altai-Sayan (275 species) orobiomes. For reptiles, it is the Dagestan orobiome (31 species) and the Caspian desert-steppe biome (37 species). For amphibians, it is the Dnieper-Volga biome, which includes the Kaliningrad region (13 species).