On this site, you can search for multimedia, specimens (collection specimens) and taxa (species descriptions of animals, plants, fungi), fossils, minerals and rocks.

The information will be supplied from the catalogues of Naturalis Biodiversity Center in Leiden, from the Dutch Species Register and the Catalogue of Life.

On practically every specimen-page a PURL (Persistent Uniform Resource Locator) is present. You can cite the object described here by using this PURL. Naturalis will try to assure the permanent character of this PURL.

The BioPortal offers four possibilities for browsing this data:


Simple Search

Bioportal works in the same way as other well-known search engines: it uses your search terms to browse our sources. Within its search operations, it will examine all the fields specified in the advanced search (such as popular name, scientific name or discovery location) and will even browse fields not accessible via the advanced search.

If you type more than one search term, we will display all the results in which one, some or all of the terms occur, but we will head the list with results with the best match.

When you make a simple search the search term will be analyzed and if there are more terms the search is divided into various parts. All these parts lead to potential search results and are combined with an OR, which can lead to very big search result sets.

It is not possible to use brackets, double-quotes or so-called wildcards to constrict or widen your searchterms. All foreign characters will be ignored in the query. To combine search terms, use the Advanced Search option.

Advanced Search

By clicking on the triangle symbol in the entry field, you will leave the simple search application, and start an advanced search. This means that you will limit your results to the category in which you are searching (multimedia, specimen or taxon) and to the specific fields in which you are searching.

If you enter search terms for more than one category, the result for each category will be shown.

When entering multiple search terms in the same category, you can use the ‘Combine search terms’ switch to influence the behaviour of the search engine. Choose 'Or' for results that include one or more of these terms, or ‘And’ for results that contain all terms.

Within the categories specimens and multimedia, you also have the option to restrict your search to a specific collection by selecting its name in the Collection name field. You can also limit your query for the categories Collection specimens, Taxa and Multimedia by selecting a specific Source (e.g. Botany or Zoology and Geology catalogues).

Geographic Search

You can use a geographic search to rapidly limit the number of search results to a particular area. The area can be selected from a list of areas on the right-hand side of the map, or drawn onto the map.

The results will always be limited to collection specimens and multimedia. Within this search type, only those results for which the geographical coordinates of the discovery location are stored in the source systems will be displayed.

We make use of a range of different sources. This means that in some cases, areas may be listed more than once. These areas will often differ in terms of degree of detail of the boundaries.

Explore Highlights

A simple and rapid search method is ‘Explore Highlights’. This search will result in a reproduction of all specimens that belong to one of the Special Collections at Naturalis. The results will be displayed immediately.

Search results

The aim of BioPortal is to deliver the results you are looking for quickly, and with that in mind, the system will use ranking.


Search results are sorted using an internal algorithm that primarily takes into account the level of uniqueness of the search terms within the entire index.

Multimedia for specimens

When you search for specimen through the advanced search form, there will appear an additional link underneath the search results, 'Show all n media items for this query'. Using this link, you can access all multimedia objects associated with the specimens in the resultset of your original search action. Please note: the advanced search form for specimen allows for searching a broader set of fields than that for multimedia. However, the function described above allows you to indirectly execute more advanced multimedia searches.

Displaying specimen results

In the screen displaying search results from the specimen index you can switch between two display modes: 'Display by specimen', which lists the results as one long list, giving you an overview of all found specimen. Alternatively, you can choose 'Display by scientific name', which lists the results grouped by scientific name, which allows you to quicky assess the different species for which specimens have been found.