Fungi assessed on the IUCN Red List

Exactly 1,300 is the number of fungal species included in the IUCN Red List update of 27 March 2025. Within that group at least 411 were considered threatened with extinction. The number assessed is not the number of all threatened fungi in the world; it shows only the fragment of the kingdom that has been through a documented assessment process.

An assessment combines information on range, abundance, population trend, habitat and threats. Threat categories are not a simple ranking of rarity, and "not assessed" does not mean safe. For many fungi regular data is lacking, because fruiting bodies appear irregularly, taxonomy changes, and observations are spatially uneven. The Data Deficient category likewise signals a gap, not a good situation.

Comparison with more than 150,000 described species shows the scale of the shortfall: fewer than one per cent have been formally assessed. It cannot be assumed, however, that the proportion of 411 out of 1,300 represents the whole kingdom. Species with better data or a suspected risk are more often selected for assessment, so the sample is not random. Applying its percentage to millions of undescribed fungi would be baseless.

The statistic has two uses. It shows concrete progress — the number of assessments has passed an important threshold — and at the same time measures the backlog in nature conservation. Further assessments require taxonomy, collections, monitoring of sites and knowledge of habitats. The date attached to the value is crucial, because the Red List is updated. MykoRadar does not present 1,300 as a running counter for all time, but as a verified state on a stated day, together with the number of threatened species.

Two questions: how many were assessed and how many are threatened

The IUCN update of 27 March 2025 raised the number of assessed fungal species to 1,300. At least 411 of that set fell into categories threatened with extinction, or at least 31.6% of those assessed. This percentage must not be projected across the whole kingdom: assessed species are not a random sample, and more than 99% of known fungi still lacked a formal assessment.

The visual therefore separates the assessed set from its threatened subset. A separate 0.6% statistic answers the coverage question for all species known to science and uses a different denominator.

What “at least” means

The IUCN release gives 1,300 as the exact size of the assessed set in that update, but 411 as a lower bound for threatened species. The corresponding share is therefore “at least 31.6%,” not exactly 31.6%. The inequality remains visible in the lead, method and evidence graphic.