Species Catalogue and Geodatabase


The aim of the Catalogue is to provide a comprehensive list of alien organisms occurring in Europe, including i) taxonomic classification, ii) the year and country of first introduction in Europe, iii) origin and native distribution, and iv) main pathways of introduction. A species is added to the Catalogue when alien (see Terms and definitions) to Europe (e.g. 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 controlled by taxonomic and thematic specialists (e.g. EASIN Editorial Board members and experts (Tsiamis et al., 2016)), responsible for revising the quality of the information for recorded alien taxa. The database managers ensure the taxonomic quality and consistency of the taxa records within the Catalogue and in relation to external data partners (Gatto et al., 2013)

1. Species scientific name and authorship

In the Catalogue, the taxon’s scientific name is set to 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).

Terrestrial Freshwater Marine
Animalia CoL, ITIS, GBIF, Avibase CoL, ITIS, GBIF, Freshwater Biodiversity Data Portal, FishBase1, Avibase WorMS, CoL, GBIF, FishBase, Avibase
Plantae World Flora Online, CoL, ITIS, GBIF, Algaebase, International Plant Names Index, EPPO World Flora Online, CoL, ITIS, GBIF, Algaebase, International Plant Names Index, Freshwater Biodiversity Data Portal WorMS, CoL, GBIF, Algaebase, International Plant Names Index, World Flora Online
Viruses CoL, GBIF CoL, GBIF WorMS, CoL, GBIF

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.

The species’ names are standardized according to the binomial and international nomenclature, i.e. International Code of Botanical Nomenclature, the International Code of Zoological Nomenclature and the International Code of Nomenclature of Bacteria. Names higher than species rank are deleted. When binomial name is not applicable, the following changes are made:

  • subgenus is indicated by subg. for algae, fungi and plants: ex. Solanum subg. Leptostemonum. (ICBN Art. 22.1)

  • subgenus is indicated within parenthesis for animals: ex. Branchiostoma (Amphioxus) lanceolatum. (ICBN Art. 25.1)

  • ssp., sub. and subspecies are replaced by subsp. for algae, fungi and plants: ex. Helichrysum strechas subsp. barrelieri. (ICBN Art. 5.A.1)

  • subspecies is indicated without parenthesis for animals: ex. Ornithoptera priamus priamus. (ICZN Art. 6.1 - modified)

  • variant is replaced by var. for algae, fungi and plants: ex., Magnolia virginiana var. foetida. (ICBN Art. 5.A.1)

  • forma is replaced by f.; forma specialis was replaced by f. sp.

  • sensu lato was replaced by s.l.;

  • cfr. is replaced by cf.;

  • × (used for hybrids and nothotaxa) is replaced by x. The letter " x" should be in lower case. A single letter space should be left between it and the epithet to avoid ambiguity ex. Mentha x piperita (nothospecies); x Apogropon lutosus (nothogenera), Dianthus caryophyllus x gratianopolitanus x plumarius (hybrid formula for taxon that has not a binomial name). (ICBN Art. H3A.1)

  • pathovar is replaced by pv. (for bacteria) ex. Xanthomonas axonopodis pv. citri

  • cultivar status cv. preceding a cultivar is no longer used and it is replaced by single quotation marks ‘’. The name is not written in Italics, it starts with a capital letter and is not a Latin name but rather a common name ex. Pinus sylvestris ‘Repens’ (ICNCP 8th Edition 2009. Art. 14.1).

1.1 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.

1.2 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).

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

Negative impacts of the alien species on the economy, livelihood, ecosystem, and human health is reported in the Catalogue under the class ‘high impact’, or ‘low/unknown’. This information is qualitative and compiled from external sources, i.e. DAISIE, CABI, GISD, NOBANIS, MedPAN, and SEBI-2010, which avails of specialists for assessing species’ impact (e.g. IUCN SSC Invasive Species Specialist Group for CABI). Details on the type of impact is not provided. The alien species included in the list of Union concern by the Commission Regulations implementing EU Regulation 1143/2014 are classified as ‘high’ impact. This qualitative classification 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.

7. 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).

List of terms and definitions for EASIN web tools and services.

alien species: Article 3 (1) of the Regulation (EU) No 1143/2014/EC: “…means any live specimen of a species, subspecies or lower taxon of animals, plants, fungi or micro- organisms introduced outside its natural range; it includes any part, gametes, seeds, eggs or propagules of such species, as well as any hybrids, varieties or breeds that might survive and subsequently reproduce…”. In addition to the IAS regulation, the definition in the EASIN context includes organisms that have entered by human agency (intentionally or unintentionally) into an area outside their natural range.

alien range: the geographical area where the alien species occurs and reproduces.

area: a biogeographic or administrative boundary where species have natural, native or alien distribution.

biogeographic barrier: barriers which prevent natural dispersal of species (Wilson et al., 2009). These can be for example physical (i.e. mountain, seawater), climatic (e.g. temperature).

biogeographic status: criteria for assessing whether a species is native or alien, i.e. biogeographic barriers, human agency, the role of human assistance for survival, and time since introduction (Essl et al., 2018).

casual alien species: alien species that “can reproduce sexually or vegetatively, but fail to maintain their populations over longer periods” (Richardson et al., 2000). Similar terms in the literatures are ‘transient’, ‘occasional escapes’, ‘waifs’.

contaminant: CBD (2014) refers to “unintentional movement of live organisms as contaminants of a commodity that is intentionally transferred through international trade, development assistance, or emergency relief. This includes pests and diseases of food, seeds, timber and other products of agriculture, forestry, and fisheries as well as contaminants of other products”

corridor: CBD (2014) refers to “movement of alien organisms into a new region following the construction of transport infrastructures in whose absence spread would not have been possible. Such trans-biogeographical corridors include international canals (connecting river catchments and seas) and transboundary tunnels linking mountain valleys or oceanic islands”

cryptogenic: species for which details on the alien status in a region are available but for which explicit evidence is lacking, implying that the species could be native (Carlton, 1996).

ecosystem: “A dynamic complex of plant, animal and micro-organism communities and their non-living environment interacting as a functional unit” (IPBES).

ecosystem services: direct and indirect benefits of ecosystems to human wellbeing (TEEB Foundations, 2010).

escape: CBD (2014) refers to “movement of (potentially) invasive alien species from confinement (e.g., from zoos; aquaria; botanic gardens; agriculture; horticulture; aquaculture and mariculture facilities; scientific research or breeding programmes; or from keeping as pets) into the natural environment.”

Europe (geographical definition): EASIN Catalogue and Geodatabase include alien species occurring in 27 EU Member States, 5 Candidate countries to the European Union, and 32 other neighbouring countries.

first record: year of first record in the wild in Europe.

invasion: spread into areas away from sites of introduction (Richardson et al., 2000).

high-impact alien species: alien species classified as ‘high-impact’ or ‘worst invasive’ in DAISIE, GISD, and SEBI-2010.

invasive alien species (IAS): Art 3 (3) of Regulation (EU) No 1143/2014/EC: “alien species whose introduction or spread has been found to threaten or adversely impact upon biodiversity and related ecosystem services”.

IAS of EU concern: Art 3 (3) of the Regulation (EU) No 1143/2014/EC: “an invasive alien species whose adverse impact has been deemed such as to require concerted action at Union level pursuant to Article 4(3)”.

IAS of MS concern: Art 3 (4) of the Regulation (EU) No 1143/2014/EC: “an invasive alien species other than an invasive alien species of Union concern, for which a Member State considers on the basis of scientific evidence that the adverse impact of its release and spread, even where not fully ascertained, is of significance for its territory, or part of it, and requires action at the level of that Member State”.

invasive non-indigenous species: invasive alien species within the meaning of Article 3(2) of Regulation (EU) No 1143/2014/EC.

introduction: Art 3 (7) of the Regulation (EU) No 1143/2014/EC: “the movement, as a consequence of human intervention, of a species outside its natural range”.

native range: the geographical area where the species naturally occurs (no intentional or unintentional introduction by human) and has naturally lived in recent times. There is not yet a formal definition (Blackburn et al., 2011; Richardson, 2011).

natural range: the geographical area where the species naturally occurs (no intentional or unintentional introduction by human) and has naturally lived in recent times (CBD, 2002). Native range can be a part of the natural range or match the same area. If the population died out and the species has no longer the potential to re-colonise without human help, these se locations form part of the natural range but not the native range.

naturalization of alien species: informs on the invasion stage and indicates alien species that establish new self-perpetuating populations without human assistance to reproduction or dispersal in the wild (Richardson et al., 2000). Synonym of ‘established alien species’.

partly native: species whose native range extends in Europe. These species can be native or alien within Europe, according to the species biogeographic status.

pathway: Art 3 (11) of the Regulation (EU) No 1143/2014/EC: “the routes and mechanisms of the introduction and spread of invasive alien species”.

questionable: in the EASIN context, these are species not verified by experts or species with unresolved taxonomic status.

release: CBD (2014) refers to “the intentional introduction in the natural environment of live alien organisms for the purpose of human use”. Examples include for biological control, erosion control (and dune stabilization), for fishing or hunting in the wild; landscape “improvement” and introduction of threatened organisms for conservation purposes”.

self-perpetuating/self-sustaining population: the capability of the species to remain stable or increase over time without human help reproducing or dispersing in the wild (Scott et al., 2005).

stowaway: CBD (2014) refers to “the moving of live organisms attached to transporting vessels and associated equipment and media. The physical means of transport-stowaway include various conveyances, ballast water and sediments, biofouling of ships, boats, offshore oil and gas platforms and other water vessels, dredging, angling or fishing equipment, civil aviation, sea and air containers. Stowaways of any other vehicles and equipment for human activities, in military activities, emergency relief, aid and response, international development assistance, waste dispersal, recreational boating, tourism (e.g., tourists and their luggage) are also included under this pathway”.

unaided: CBD (2014) refers to “the secondary natural dispersal of invasive alien species that have been introduced by means of any of the foregoing pathways”.

widely spread species: Art 3 (16) of the Regulation (EU) No 1143/2014/EC: “an invasive alien species whose population has gone beyond the naturalisation stage, in which a population is self-sustaining, and has spread to colonise a large part of the potential range where it can survive and reproduce”.

Blackburn, T.M., Pysek, P., Bacher, S., Carlton, J.T., Duncan, R.P., Jarosık, V., Wilson, J.R.U., Richardson, D.M. (2011). A proposed unified framework for biological invasions. Trends in Ecology & Evolution, 26, 333–339

Carlton, J. T. (1996). Biological invasions and cryptogenic species. Ecology, 77(6), 1653-1655.

CBD. (2014). Pathways of introduction of invasive species, their prioritization and management. Montréal: Secretariat of the Convention on Biological Diversity.

CBD (2002). https://www.cbd.int/decision/cop/?id=7197

Essl, F., Bacher, S., Genovesi, P., Hulme, P. E., Jeschke, J. M., Katsanevakis, S., ... & Richardson, D. M. (2018). Which taxa are alien? Criteria, applications, and uncertainties. BioScience, 68(7), 496-509.

Gatto, F., Katsanevakis, S., Vandekerkhove, J., Zenetos, A., & Cardoso, A. C. (2013). Evaluation of online information sources on alien species in europe: The need of harmonization and integration. Environmental Management, 51(6), 1137–1146. https://doi.org/10.1007/s00267-013-0042-8

Harrower, C. A., Scalera, R., Pagad, S., Schonrogge, K., & Roy, H. E. (2018). Guidance for interpretation of CBD categories on introduction pathways.

Hulme, P. E., Bacher, S., Kenis, M., Klotz, S., Kühn, I., Minchin, D., ... & Vilà, M. (2008). Grasping at the routes of biological invasions: a framework for integrating pathways into policy. Journal of Applied Ecology, 45(2), 403-414.

Katsanevakis, S., Bogucarskis, K., Gatto, F., Vandekerkhove, J., Deriu, I., & Cardoso, A. C. (2012). Building the European Alien Species Information Network (EASIN): A novel approach for the exploration of distributed alien species data. BioInvasions Records, 1(4), 235–245. https://doi.org/10.3391/bir.2012.1.4.01

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Tsiamis, K., Zenetos, A., Deriu, I., Gervasini, E., & Cardoso, A. C. (2018). The native distribution range of the European marine non-indigenous species. Aquatic Invasions, 13(2), 187–198. https://doi.org/10.3391/ai.2018.13.2.01

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