Data

Number of described species

IUCN
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What you should know about this indicator

  • Since many species have not yet been described, this is a large underestimate of the total number of species in the world.
  • For a species to be formally described, it's description must be published in a scientific journal or book.
  • Species descriptions should fulfill several criteria specified by the relevant nomencalture code, including the selection of a type specimen, a particular specimen formally associated with scientific name and description.
  • The values of the numbers of described species should be used with caution as these are not always be up to date for all taxonomic groups.
  • The source for each taxonomic group can be found in the IUCN Red List summary statistics, Table 1a.
  • The 'mushrooms' taxonomic group includes brackets, rusts, smuts and, jelly fungi.
Number of described species IUCN
The number of formally identified, described and named species in each .
Source
International Union for Conservation of Nature (IUCN) Red List (2022) – with minor processing by Our World in Data
Last updated
December 8, 2022
Next expected update
July 2024
Date range
2020–2022
Unit
species

Sources and processing

This data is based on the following sources

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.

Retrieved on
December 8, 2022
Citation
This is the citation of the original data obtained from the source, prior to any processing or adaptation by Our World in Data. To cite data downloaded from this page, please use the suggested citation given in Reuse This Work below.
IUCN. 2023. The IUCN Red List of Threatened Species. https://www.iucnredlist.org.

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Citations

How to cite this page

To cite this page overall, including any descriptions, FAQs or explanations of the data authored by Our World in Data, please use the following citation:

“Data Page: Number of described species”, part of the following publication: Hannah Ritchie, Fiona Spooner and Max Roser (2022) - “Biodiversity”. Data adapted from International Union for Conservation of Nature (IUCN) Red List. Retrieved from https://ourworldindata.org/grapher/number-of-described-species [online resource]
How to cite this data

In-line citationIf you have limited space (e.g. in data visualizations), you can use this abbreviated in-line citation:

International Union for Conservation of Nature (IUCN) Red List (2022) – with minor processing by Our World in Data

Full citation

International Union for Conservation of Nature (IUCN) Red List (2022) – with minor processing by Our World in Data. “Number of described species – IUCN” [dataset]. International Union for Conservation of Nature (IUCN) Red List, “Threatened and evaluated species (IUCN Red List)” [original data]. Retrieved June 22, 2024 from https://ourworldindata.org/grapher/number-of-described-species