FORMIDABEL; The Belgian Ants Database

ZooKeys 306: 59–70, doi: 10.3897/zookeys.306.4898

Resource citation

Polyergus Working Group (  and FormisWalBru working group ( (2013 -). FORMIDABEL: The Belgian Ants Database, 27264 records. Contributed by Dimitri Brosens (Processor), François Vankerkhoven (Content Provider), David Ignace (Content Provider), Philippe Wegnez (Content Provider), Nicolas Noé (Processor), André Heughebaert (Processor), Jeannine Bortels (Content provider), Wouter Dekoninck (Principal investigator), Online and , , Version 1.0 (last updated on 2013-04-19),

GBIF key:


FORMIDABEL is a database of Belgian Ants containing more than 27.000 occurrence records. These records originate from collections, field sampling and literature. The database gives information on 76 native and 9 introduced ant species found in Belgium. The collection records originated mainly from the Ants collection in Royal Belgian Institute of Natural Sciences (RBINS), the ‘Gaspar’ Ants collection in Gembloux and the zoological collection of the University of Liège (ULG). The oldest occurrences date back from May 1866, the most recent refer to August 2012. FORMIDABEL is a work in progress and the database is updated on a regular basis. Twice a year the database is updated with data from the North and the South of the country.

The latest version of the dataset is publicly and freely accessible through this url: The dataset is also retrievable via the GBIF data portal through this link: A dedicated geo-portal, developed by the Belgian Biodiversity Platform is accessible at:


Purpose: FORMIDABEL is a joint cooperation of the Flemish ants working group "Polyergus" ( and the Wallonian ants working group "FourmisWalBru" ( The original database was created in 2002 in the context of the preliminary red data book of Flemish Ants (Dekoninck et al. 2003). Later, in 2005, data from the Southern part of Belgium; Wallonia and Brussels were added. In 2012 this dataset was again updated for the creation of the first Belgian Ants Atlas (Dekoninck et al. 2012). The main purpose of this atlas was to generate maps for all outdoor living ant-species in Belgium using an overlay of the standard used Belgian ecoregions. By using this overlay for most species, we see a clear and often restricted distribution pattern in Belgium, mainly based on existing vegetation and soil types.

Keywords: Formicidae, Belgium, Flanders, Wallonia, Brussels Capital Region, ecological data, grid mapping, UTM, historical data, literature, collections, observations, trapping, ants

Data published through

Taxonomic coverage

General taxonomic coverage description

The taxonomic coverage (figure 2) of this database spans the full range of ants pertaining to Belgium (indigenous ant species and exotic introduced species). The determination level is species level and if appropriate also hybrid level. For some species, information on micro-and macrogynes is available in FORMIDABEL Key milestones of FORMIDABEL from conception till date are described in the ”Dataset” section of this manuscript. The taxonomic authorities followed are: Radchenko & Elmes (2010) for the genus Myrmica and Seifert (2007) for the other genera. De dataset contains occurrences of 76 native and 9 introduced species.

As depicted in Figure 1, the most abundant subfamily in the database is the Formicinae (49,4%) followed by the Myrmicinae (48,7%), the Dolichoderinae (0,9%) and the Ponerinae (0,8%). The top five most recorded species are Lasius niger (2846 records), Myrmica rubra (2601 records), Myrmica scabrinodis (1626 records), Formica fusca (1467 records) and Myrmica sabuleti (1202 records).

fig2   Taxonomic ranks

  • Phylum: Arthropoda
  • Subphylum: Hexapoda
  • Class: Insecta
  • Order: Hymenoptera
  • Suborder: Apocrita
  • Superfamily: Vespoidea
  • Family: Formicidae
  • Subfamily: Dolichoderinae, Formicinae, Myrmicinae, Ponerinae
  • Genera: Anergates, Aphaenogaster, Camponotus, Dolichoderus, Formica, Formicoxenus, Harpagoxenus, Hypoponera, Lasius, Leptothorax, Linepithema, Manica, Monomorium, Myrmecina, Myrmica, Plagiolepis, Polyergus, Ponera, Solenopsis, Stenamma, Strongylognathus, Tapinoma, Technomyrmex, Temnothorax and Tetramorium.

    Common names: Ants

    Spatial coverage

    General spatial coverage

    Belgium is a small country in Western Europe. To the west, its 70 km coastline fronts the North Sea; to the north lies the Netherlands; to the east, Germany, and to the south, France and Luxembourg. Biologically, the fauna of eastern Belgium belongs to the Central European Province of the Eurasian (Palaearctic) Region. By contrast, the rest of the country primarily consists of an Atlantic fauna plus a few Central European relict species.

    Politically and geographically, the country is divided into three parts: Flanders, Wallonia and the Brussels Capital Region. In Flanders (13,522 km² and population about 6 million people), to the north, soils are mainly sandy to loamy. Here, the most important habitats for ants are heathlands and dry grasslands. The Brussels Capital Region is a small region (162 km²) within Flanders and is entirely situated in the sandy loam area. In Wallonia (17,006 km² and about 3,5 million people), to the south, soils and habitats are more diverse, ranging from forests to rocky and calcareous grasslands on loam and chalky soils. Eastern Wallonia, near the German border, includes the Hautes Fagnes, a large area of bogs and peat with some typical ant species.

    Geographical method

    The Universal Transverse Mercator Projection (UTM), an adaptation of the standard Mercator projection, uses a two dimensional Cartesian co-ordinate system to identify locations on the surface of the Earth (Wikipedia).

    The UTM 5 Km (Universal Transverse Mercator Projection) raster projection divides Belgium in approximately 1200 25 km² squares. A representative number of UTM squares has been sampled (1125 UTM 5x5 km squares of which 659 squares with more than 10 records see also Figure 3 & 4) to complete the dataset. All the records in FORMIDABEL are georeferenced through the centroid coordinates of the corresponding UTM 5 km square. Therefore, the uncertainty of these coordinates is 3.500 meters, the distance between the centre and the corner of the UTM square.

    Figure 3

    Figure 4


    More than half of the records are provided with an description of the microhabitat of the record locality. This allows us to give details on ecological preferences of all Belgian ant species. In FORMIDABEL we created a list of potential microhabitats for ants in Belgium. For each of these microhabitats we use a code called the “ecocode”. This code thus gives information on the habitat were the occurrence was made. Nine types of habitat and landscape were defined to collect accurate information on the habitat preference of all ant species (Dekoninck et al, 2005). The nine types were based on the EIS-code and the Flemish nature types (Vandenbussche, 2002; Zwaenepoel et al. 2002). When no habitat description was available for a record (for example, with some older records) the habitat was coded as ‘Not known or not observed’. The nine main habitats we defined were: i) anthropogenic habitats, ii) dry grasslands, iii) moist grasslands, iv) forests, v) chalk grasslands stony slopes and other rocky xerothermic habitats, vi) shrubs, vii) heathlands, viii) –fens and highland bogs and ix) coastal and inland dunes.


    49°27'0''N and 51°32'24''N Latitude; 2°28'12''E and 6°27'36''E Longitude

    Temporal coverage

    The oldest record in the database goes back to May 5, 1866 and the most recent records are from August 2012. The largest part of the records were retrieved after 1991 (see Figure 5).

    Figure 5


    Method step description:

    A large portion of the occurrence data have been sampled by volunteers, other records originated from several projects and research programs. The data and specimens were sent to the Belgian ant curators and after validation, the information was incorporated in the database. The collection records “dry specimen” originate from the Gembloux “Ant” collection and the Charles Gaspar collection, the collection of the “Cercle des entomologist Liégeois”, the RBINS collection and the private collection “Roland Vannieuwenhuyse”. After revision and validation, this information was also embedded in the database. The literature based records were retrieved from van Boven, 1970; van Boven & Mabelis, 1986; Dekoninck et al., 2006 and references therein. How the database evolved is described in the Database history section.

    Sampling description: Most occurrence records originate from hand/nest sampling (42,3% of all records and mainly from Wallonia) and pitfall sampling (36,7% mainly from Flanders). The followed procedure differs from region to region. This is due to historical reasons. Some very interesting occurrence records were retrieved from sifting, coloured water traps and Malaise traps (all less than 3 % of the total sampling). An extended description of the sampling methods is described in Collecting And Preserving Insects And Mites Techniques And Tools by M. E. Schauff (2001)

    Quality control description: All the records were validated by the dataset curators before they were added to the FORMIDABEL database. The dataset curators also checked all the determinations of the collection specimens. If needed, the determination was adapted and made consistent with modern taxonomy; Radchenko & Elmes (2010) for the genus Myrmica and Seifert (2007) for the other genera. Before the final publication of the database all the records were tested on geographical consistency by the Belgian Biodiversity Platform and adapted if appropriate.


    Dataset History

    At the beginning of 2001 all available records of ants in Flanders (northern part of Belgium) were brought together for the first time and several inventories were started. More than 20.000 records (for the most part gathered after 1990) were assembled in the FORMIDABEL (FORMIcidaeDAtaBELgium) database  resulting in the ‘Verspreidingsatlas en voorlopige Rode lijst van de mieren van Vlaanderen; Dekoninck et al. 2003. [Distribution atlas and preliminary Red list of ant species in Flanders, Belgium]. This report contains all available distribution data for Flanders. In the southern part of Belgium (Wallonia) intensive inventorying started in 2005. Until then knowledge on the distribution of ants in Wallonia was limited. Only a few areas (Haute Fagnes, Famenne and the Viroin valley) were already inventoried. Thanks to the good cooperation between the Polyergus and the FourmisWalBru working groups many Belgian ant records were brought together in the FORMIDABEL database. Since then, the FORMIDABEL is updated with data originating from FourmisWalBru twice a year. The FORMIDABEL dataset was then used for the creation of the “Belgian Ant Atlas”, (Dekoninck et al. 2012). In 2010 a cooperation  agreement between the authors of the atlas and the Belgian Biodiversity Platform ( was made. Together with the publication of the book, the data was published in Darwin Core Archives to GBIF (url:  and a dedicated data portal was created:  

    The original FORMIDABEL database was created in Microsoft Access. Later, this database was completely imported in a relational SQL database. During this process additional data cleaning was performed; see section Quality control description. The dataflow is illustrated in figure 6.

    Image 6

    Dataset description

    The FORMIDABEL Darwin Core Archive is a custom made SQL view on the original version of the FORMIDABEL access database which is in the custody of the Belgian Ant working group Polyergus. Mind that every record in FORMIDABEL represent at least one occurrence, but primarily contains information on the presence of a species. The view only shows data that are accepted for publication. Fields given are:

    id, decimalLatitude, family, basisOfRecord, stateProvince,identifiedBy, eventDate, modified, country, individualCount, scientificName, kingdom, order, geodeticDatum, genus, collectionCode, decimalLongitude, samplingProtocol, catalogNumber, phylum, recordNumber, countryCode, coordinatePrecision, language, coordinateUncertaintyInMeters, locality, specificEpithet, recordedBy, institutionCode, nomenclaturalCode, class

    The dataset contains primary biodiversity data, mostly occurrence data. Some records hold an indirect link to collection specimens. This link is only available in the original database.

    Norms for data use and publication:

    Since January 20th 2015 the data is republished under CC0, please keep the following norms in mind when using or reusing the data

    Based on

    • Give credit where credit is due
    • As is common practice in scientific research, cite the data you are using
    • Be responsible
    • Use the data responsibly. The data are published to allow anyone to better study and understand the world around us, so please do not use the data in any way that is unlawful, harmful or misleading. Understand that the data are subject to change, errors and sampling bias. Protect the reputation of the data publisher and clearly indicate any changes you may have made to the data
    • Share knowledge
    • Let us know if you have used the data. It helps our participants to showcase their efforts and it helps you reach a wider audience. Inform the data publisher(s) if you have comments about the data, notice errors, or want more information
    • Respect the data license
    • Understand and respect the data license or waiver under which the data are published. It is indicated in the rights field of every record and in the dataset metadata

    Collection data: Ant Collection Gembloux (, Collection Charles Gaspar, Collection “Cercle des entomologists Liégeois”, RBINS Belgian Formicidae Collection ( ), Private collection “Van Nieuwenhuyse”. All collections are dry prepared insect collections. The dataset does not contain unique identifiers for specimens. To track a collection specimen, the corresponding author should be contacted.

    Additional information

    This dataset was originally created to develop the Belgian Ants Atlas. However, the dataset can be reused for a variety of purposes. Since the link between individual data records and underlined specimens (stored in multiple collections) is not recorded, we doubt if the dataset can be used for taxonomic or systematic studies. However, this being the occurrence dataset, it can be used for understanding species richness, distribution pattern and modeling studies such as ecological niche modeling. In order to enhance the confidence of use, we have documented the metadata as well subjected the data records through a series of quality assessment and enhancement processes as described in the earlier section quality descriptions.


    The authors would like to thank all the contributors to this data paper. Especially all the volunteers who spend hours in the field collecting ants. We would also like to thank the Entomology Department of RBINS (Dr. Patrick Grootaert), the Cercle des Entomologistes Liégeois (P. Lays) and Gembloux Agro-Bio Tech, Unité d’Entomologie fonctionnelle et évolutive for giving us access to the collections and the Belgian Biodiversity Platform and GBIF to make this work possible. Last but not least we would like to thank Thomas Little for making sure that the English language was respected during the creation of this paper.