European Commission logo
EASIN - European Alien Species Information Network

Species Catalogue and Geodatabase


The aim of this document is to provide guidelines to collect and compile alien taxa details for the update of the EASIN Catalogue.

The aim of the Catalogue is to provide a comprehensive list of alien taxa occurring in Europe, including their i) taxonomic classification, ii) the year and country of first introduction in Europe, iii) origin and native range, and iv) main pathways of introduction. A species is added to the Catalogue when alien (see Terms and definitions) to Europe (native range outside Europe, an extent defined by 27 EU Member States, 5 Candidate countries to the European Union, and 32 other neighbouring countries) or to some European countries (i.e. partly native- see Terms and definitions) and observed in the wild. Data on alien taxa kept in captivity (i.e. zoos botanic gardens, gardens, aquariums, and greenhouses) are not recorded.

The content of the EASIN Catalogue is ensured by taxonomic and thematic specialists (e.g. EASIN Editorial Board members and other experts (Gatto et al., 2013; Tsiamis et al., 2016)), entrusted with specific responsibilities for revising the quality of the information for recorded alien taxa. The JRC Team ensure the overall taxonomic quality and consistency of the taxa records within the Catalogue.

The Catalogue is regularly updated based on new data availability.

1. EASIN Identifier (ID)

Each species or subspecies with an accepted (valid) scientific name is identified by an ID code, denoted as ‘Rxxxxx’. It is a progressive ID code of one letter, i.e. “record (R)” and 5 digits, ensuring distinct and unique species identification.

When the taxonomy of a species should change, for example when a species’ scientific name (latin, binomial) would be reassigned, with changes in the genus or species, the EASIN ID will not be changed. The previous species’ accepted name will be moved to the Catalogue line ‘synonyms’, remaining still retrievable through the “Species Search” and “Web Services” tools. This is of particular relevance when species are mentioned in the legislation (e.g. Regulation (EU) 1143/2014) with a scientific name no longer accepted by the scientific community.

1.1 Life Science Identifier (LSID)

Each species of the Catalogue is identified by a unique LSID to enable its location and interoperability across multiple distributed data sources. EASIN LSID conforms to the URN (Universal Resource Name) standards following the format:[Rxxxxx]. EASIN LSID is reported across EASIN tools: Species Search, Species Mapper, and Species Factsheets.

1.2 Species scientific name and authorship

In the Catalogue, the taxon’s scientific name is described by the binomial nomenclature (i.e. genus name= Sciurus and specific epithet= vulgaris). Scientific name and authorship are retrieved and verified from international databases and data infrastructures that provide access to marine, freshwater and terrestrial organisms’ taxonomy and systematics (Table 1).

Taxon autonyms of subspecies (subsp.), varietas (var.) of taxa are record ed (e.g. Lupinus albus subsp. albus), and their validity checked from international data infrastructures (Section 1.1., Table 1) as a guide to interpret taxonomic literature.

Taxon synonyms are recorded, and their validity checked from international data infrastructures (Table 1). For species of Union concern (under EU Reg. 1143/2014), characterized by multiple valid names (e.g. Koenigia polystachya), the Catalogue reports also the corresponding scientific name of the Commission Implementing Regulation.

Finally, the taxon vernacular names are added.

1.3 Classification in taxonomic ranks

The taxonomic hierarchy adopted in the Catalogue for cellular organisms (i.e. Bacteria, Protozoa, Chromista, Plantae, Fungi, Animalia) follows the classification proposed by Cavalier-Smith (2004). Additionally, the categories ‘viruses’ (non-cellular forms) and ‘unresolved’ (taxa with yet unresolved taxonomy) are included. Several international sources (Table 1) are used for the compilation of the taxonomic ranks, and a literature search is carried out when the classification cannot be resolved. A citation is included for each taxon to provide information on the source that has been used to create it.

1.4 Taxon status

Three taxon statuses are defined and assigned to the taxa: Alien (i.e. species introduced outside its native range), Cryptogenic (i.e. species with unknown native range or pathway of introduction), Questionable (i.e. species with unresolved taxonomic status or not verified by experts) (see Terms and definitions). The Catalogue includes partly native species, as defined in Terms and definitions.

2. Environment

For each taxon in the Catalogue, the environments where the species lives are added. This information is often available from the data infrastructures listed in Table 1 or by looking at additional regional databases and portals. For unresolved taxon, the environment is added based on literature search.

3. First introduction in Europe

For each species the date of first introduction (see Terms and Definitions) in Europe is specified. If this information is not available, the Catalogue records the year of the paper publication. For marine species, information on first introduction at country level is also provided.

4. Distribution: origin

The species’ status is detailed with information on the species’ native range in Europe following the approach of Katsanevakis et al. (2012). This data is obtained by literature review and revised by taxonomic and thematic experts. The species sheet reports the list of Member States (for terrestrial and freshwater species) or the marine ecoregions (for marine organisms) where the species has its native range in Europe.

The origin of the alien species outside Europe is also reported (Tsiamis et al., 2018) using the United Nations geoscheme and biogeographic regions for terrestrial and freshwater species, and the marine ecoregions according to Spalding 2006 (Vol. 57 No. 7 BioScience).

The year and the country of the first record of the species outside its native area in Europe is reported and supported by bibliographic references.

5. Pathways

The identification of pathways of introduction is based on the contribution of the thematic experts. Up to Catalogue version 8.6, the framework by Hulme et al. (2008) was used to include five main pathways (i.e. release, escape, contaminant, stowaway, corridor, and unaided - see Terms and Definitions). Currently, the classification of the Convention of the Biological Diversity (CBD, 2014) is adopted, and the species are assigned to pathways of introduction according to three main categories: i) importation of a commodity, ii) arrival of a transport vector, and iii) spread from a neighbouring region (CBD, 2014; Harrower et al., 2018).

6. Impact

The Catalogue indicates alien species with known negative impacts on the economy, livelihood, ecosystems, and human health under the 'Impact' field (boolean yes or no).
This qualitative information is compiled from various sources , i.e. DAISIE, CABI, GISD, NOBANIS, MedPAN, and SEBI-2010, which avails of specialists to assess species' impact (e.g. IUCN SSC Invasive Species Specialist Group for CABI), and is specified under the 'Impact source' field. The information on impact of invasive alien species included in the list of Union concern by the Commission Regulations implementing EU Regulation 1143/2014 is supported by in-depth assessments of experts considering species' negative effects on i) biodiversity and ecosystem, ii) ecosystem services, iii) economic, and iv) social and human health following a procedure laid down by Commission Delegated Regulation (EU) 2018/968, which link is provided under the field 'Risk Assessments (Commission Delegated Regulation (EU) 2018/968)'.

7. Horizon scanning

Horizon scanning is an approach to prioritize the emerging and most threatening IAS with the highest risk of introduction in a given region and can support the EU Member States in implementing the IAS Regulation. Species identified as “horizon scanning” are likely to constitute a severe risk to the EU biodiversity in the future based on the publication of Czechowska et al., 2022.

8. Factsheet

More detailed information about species’ traits and their impact can be retrieved from specific “factsheets”, online resources linked to the EASIN species’ description (e.g. CABI, EPPO, NOBANIS).

Share this page