Species of Fungi Recommended in the Red Data Book of the Rostov Region on the Basis of the IUCN Criteria

Using the example of the preparation of the third edition of the Red data book of the Rostov Region (section Fungi), the experience of applying criteria developed by the International Union for Conservation of Nature is presented. Until recently, the assessment of rarity and threats was carried out using traditionally accepted methods in Russia and often allowed for a significant degree of subjectivity. The IUCN criteria are based on quantitative assessments, which permit a more of accurate evaluation of species status and associated threats. The introduction of new assessment criteria frequently results in a notable revision of the lists of species proposed for protection, with the exclusion of a considerable number of species. The application of most criteria in relation to fungi is exceedingly challenging. Criterion B (geographical distribution: extent of occurrence and area of occupancy) is the most adequate, which allows to indirectly assess the degree of threat of extinction of the species in the territory under consideration. Since the IUCN criteria have been developed for assessment at the global level, it is necessary to develop clearer recommendations for work at the regional level regarding the assessment of the area of areal and habitat.