Widely used in the scientific community, the International Union for Conservation of Nature (IUCN) is an institution that currently encompasses the greatest amount of information and data on the conservation status of species of fungi, plants and animals around the world. Established in 1964, the goals described by the organization itself are: "to provide science-based information on the status of species and subspecies at a global level; to draw public attention to the magnitude and importance of threatened biodiversity; to influence national and international legislation and policies; and to provide information to guide actions to conserve biological diversity" (O ECO, 2014).
The criteria used to classify species into categories are: population size; subpopulations; mature individuals; gestational time; reduction as per estimated decline and the relationship between population and habitat loss; extent of occurrence; area of occurrence; severe fragmentation of biomes; location and quantitative analysis.
In a practical way, the analyzed living beings are divided and classified into nine categories:
1. Not evaluated (NE) - species not evaluated by the organization's criteria;
2. Deficient data (DD) - not enough data to assess the level of conservation;
3. Least Concern (LC) - when compared to the other categories, species classified as Least Concern do not present many risks of extinction;
4. Near Threatened (NT) - species that need conservation measures so that they do not become vulnerable to extinction;
5. Vulnerable (VU) - risk of becoming extinct in nature;
6. Endangered (EN) - high risk of becoming extinct in its habitat;
7. Critically Endangered (CR) - extremely high risk of becoming extinct in nature;
8. Extinct in the wild (EW) - no longer found in its natural habitat, just in captivity;
9. Extinct (EX) - no specimen is alive in the wild or in captivity.
Based on these criteria, the IUCN produces a document called the "Red List of ThreatenedSpecies" to demonstrate the degree of decline in world biodiversity. This list is an international source of information and a reliable database for evaluation and subsequent work, as it is possible to find information on the researched species such as habitat, food, weight, size, location, classification, taxonomy, bibliographies used and others so many useful informationals for the knowledge of the species. Generally speaking, this civil organization cooperates with international diversity and conservation in order to cover all studied species and their peculiarities. REFERENCES
ENTENDA A CLASSIFICAÇÃO DA LISTA VERMELHA DA IUCN. O eco, 2014. Disponível em: <https://oeco.org.br/dicionario-ambiental/27904-entenda-a-classificacao-da-lista-vermelha-da-iucn/>. Acesso em 30 de novembro de 2021. SANTOS, Vanessa Sardinha dos. Lista Vermelha de Espécies Ameaçadas da IUCN. Mundo Educação. Disponível em: <https://mundoeducacao.uol.com.br/curiosidades/lista-vermelha-especies-ameacadas-iucn.htm>. Acesso em 30 de novembro de 2021. ICMBIO - INSTITUTO CHICO MENDES. Aplicação de Critérios e Categorias da UICN na Avaliação da Fauna Brasileira. Coordenação de Avaliação do Estado de Conservação da Biodiversidade. Disponível em: <https://www.icmbio.gov.br/cepsul/images/stories/especies_ameacadas/publicacoes/2013_apostila_aplicacao_criterios_categorias_UICN_versao_2.0.pdf>. Acesso em 30 de novembro de 2021. BACKGROUND & HISTORY. IUCN RED LIST, 2021-2. Disponível em: <https://www.iucnredlist.org/about/background-history>. Acesso em 30 de novembro de 2021.