Overall, 17.9% and 21.7% of species are considered threatened in Europe and in the EU 27/28, respectively. These values assume that a similar relative proportion of the Data Deficient (DD) species are likely to be threatened, and provides the best estimation of the proportion of threatened species (IUCN 2011).
For almost one quarter of the species in Europe (168 species – 24.4%), there was not enough scientific information to evaluate their risk of extinction and they were assessed as DD. In the EU 27/28, 133 species (20.4%) were also assessed as DD. When more data become available, it is possible that many of these species may also prove to be threatened. Thus, the proportion of threatened species could lie between 13.5% (if all DD species are not threatened) and 37.9% (if all DD species are threatened) for Europe, and between 17.3% and 37.7% for the EU 27/28.
In Europe, 0.7% of species have been assessed as Critically Endangered, 7.4% as Endangered and 5.4% as Vulnerable (Table 1 and Figure 1). A further 13% (89 species) are considered Near Threatened. There is a higher proportion of threatened species in the EU 27/28 (1.1% Critically Endangered, 9.3% Endangered and 6.9% Vulnerable), with 13.5% Near Threatened (Table 1 and Figure 2).
The complete list of species and their Red List status in Europe and in the EU is available as Supplementary Material.
Table 1. Summary of numbers of saproxylic beetles within each Red List Category.
* This table does not include the Not Applicable species in Europe (5 species) and/or the EU (2 species) (species of marginal occurrence). For the EU assessments, the Not Evaluated species (species which do not occur in the EU) are also excluded.
Figure 1. IUCN Red List status of saproxylic beetles in Europe.
Figure 2. IUCN Red List status of saproxylic beetles in the EU.
Although saproxylic beetles represent an ecological grouping and are not an entire taxonomic group, by comparison, 58% of freshwater molluscs, 40% of freshwater fishes, 29% of grasshoppers, crickets and bush-crickets, 23% of amphibians, 20% of reptiles, 20% of lycopods and ferns, 17% of mammals, 16% of dragonflies, 13% of birds, 9% of butterflies and bees, 8% of aquatic plants and marine fishes, and 2% of medicinal plants are threatened, groups that were comprehensively assessed for the European region. Additional European Red Lists assessing a selection of species showed that 22% of terrestrial molluscs, and 16% of crop wild relatives are also threatened. No other groups have yet been assessed at the European level. Thus, saproxylic beetles are one of the most threatened insect groups in Europe assessed so far, with only a smaller percentage of threatened species than grasshoppers, crickets and bush-crickets.