COMPARATIVE ANALYSIS OF THE COMPOSITION OF THE TERRESTRIAL FAUNA AND FLORA OF THE TETHYS DESERT-STEPPE REGION OF PALEARARTICS, BIOGEOGRAPHIC BOUNDARIES OF THE CAUCASUS. MESSAGE 1. TERRESTRIAL FAUNA

Abstract

Aim. The aim is to conduct a comparative analysis of the composition of the terrestrial fauna of the Tethys desert-steppe region of the Palearctic. Materials and methods. The work was based on the materials collected in different republics and regions of the Caucasus and the south of the European part of Russia during 50 years (from 1961 to 2016) which are kept in various domestic and foreign institutions. Catalogs on the studied model groups were also used to conduct the research. In making the dendrograms, a cluster analysis based on the Jaccard coefficient was used. Results. A detailed analysis was carried out by model groups of the animals of the Eastern and Western Thethys complexes of the desert-steppe region of the Palearctic. Comparative analysis has shown that a significant number of species and genera of the discussed territories is characterized by an exceptionally high ratio of endemic species and superspecies taxa. Indicators of endemism in model groups fluctuate depending on the population's ability to resettle. High endemism of faunas of darkling beetles, ground beetles, click beetles and land snails in the Eastern Tethys complex was noted. Conclusion. The Caucasus (in a new interpretation) is characterized by a high percentage of endemism for the studied model groups. A large number of the common Tethys genera and species in all model groups attests to their fundamental role in the overall composition of the biota against the background of powerful autochthonous centers of species-formation and, most importantly, the formation and functioning of the Palaearctic desert-steppe belt as the Tethys ocean reduced.