The IUCN Red List Of Threatened Species

The IUCN Red List of Threatened Species is the world's most comprehensive inventory of the global conservation status of biological species. It uses a set of quantitative criteria to evaluate the extinction risk of thousands of species, classifying them into categories from "Least Concern" to "Extinct".

The IUCN Red List has assessed only a small share of the total known species in the world. This means the number of species threatened with extinction is likely to be a significant underestimate of the total number of species at risk.

This is particularly true for understudied groups such as insects, plants and fungi.

The share of known species threatened with extinction is only available for a few taxonomic groups where more than 80% of species have been assessed.

"Threatened" species are those that are categorized as "Critically endangered", "Endangered" or "Vulnerable" on the IUCN Red List.

The "mushrooms" taxonomic group includes brackets, rusts, smuts and jelly fungi.