Known issues

This page lists all issues concerning the Belgian Register of Marine Species known to the Consortium or brought to our attention by users.

Added on 2010-08-25

Bacteria not included in BeRMS (2010-08-25)

To know the number of Bacteria species present in the Belgian marine environment is an intriguing yet difficult question to answer. There are no recent reports documenting the diversity of marine Bacteria in the Belgian marine environment and all information available originates from older literature. Research in this area is just starting and will in the future provide insights into this diversity.

Over the last 5 to 10 years, a lot of changes have taken place in the field of bacterial research: improved identification techniques and new taxonomical insights have led to a better understanding of this group.

The most recent literature information available to the Belgian Register of Marine Species dates from early 2000 and goes back to 1907. Experts on the matter suspect this literature makes use of outdated taxonnames. Many bacterial taxa have in recent years been renamed or split up into several species and or genera, leading to an incorrect species list.

Keeping in mind these concerns, it was decided not to present a list of Bacteria currently documented for Belgium. In the future, we will however be able to fill this gap in our knowledge, as the Laboratory of Microbiology and the Department of Biology (UGent) have started to investigate the bacterial diversity in the Belgian marine environment.

Protozoa not included in BeRMS (2010-08-25)

The question of protist species distribution is currently hotly debated with two conflicting theories. One maintains that all free-living protists are cosmopolitan, i.e. that "everything is everywhere" and that the environment selects which will grow to form active populations. The other maintains that many species (at least 30%) are biogeographically restricted, and that evidence for this increases if one takes into account molecular diversity and the likelihood that many morphospecies are in fact complexes of sibling species.

Keeping in mind these concerns, it was decided not to present a list of Protozoa currently documented for Belgium.

Bacillariophyta not included in BeRMS (2010-08-25)

As in other groups of unicellular organisms, the last decades have seen tremendous changes in our knowledge about the biodiversity, taxonomy and biogeography of diatoms. First, detailed studies of the morphological variation during the life cycles of diatoms have shown that in the past many species have been lumped together. This has not only led to confused species identities but also to a serious underestimation of marine diatom biodiversity in general, and in the notion that most species are cosmopolitan. Second, the realization that our estimates of diversity were wrong has been confirmed by the increased use of molecular techniques. These have uncovered that many - if not most - traditionally known species (delineated on the basis of morphological features) actually consist of numerous so-called cryptic species (this means that they are difficult or impossible to distinguish using microscopy alone). Finally, the use of molecular-genetic inventarization methods (such as clone libraries and more recently large-scale sequencing projects) have shown that our current estimates of the biodiversity of marine diatom communities are too low, because especially the rare fraction of these communities is much more diverse than previously thought. In traditional microscopy-based analyses, these rare species are usually overlooked.

At present, it is not possible to evaluate the identity of many species reported in the literature, because most published data cannot be critically evaluated due to the lack of good, detailed descriptions and/or illustrations, and because molecular data are sometimes necessary to confirm the presence of a species. It is therefore advisable to create new species lists based on recent, intercalibrated diatom records from the coast. Based on future efforts, compiling a species list specific for the Belgian marine water will become possible.

Mollusca: only species with known live occurrences included in BeRMS (2010-08-25)

Not all shells found on our beach are remnants of species actually living in the Belgian part of the North Sea. Shells can travel quite some distance before washing ashore or they are fossilized.

So far, the Belgian Register of Marine Species only lists the species with known occurrences of living individuals. For an overview of all shells and fossils which can be encountered in the Belgian part of the North Sea, we refer to literature and guides dealing with this information, for example "Schelpen aan de Belgische kust" published in 2010.

Aves: only true marine birds included in BeRMS (2010-08-25)

Birds spotted at sea are numerous, but only a limited number of them can truly be identified with the marine environment for survival. The Belgian Register of Marine Species so far only lists those birds which forage at sea, forage in the intertidal area, rest at sea, depend on the sea during migration and are spotted rather rarely in the Belgian part of the North Sea.

Insecta included in BeRMS limited to eulittoral zone (2010-08-25)

So far, the Belgian Register of Marine Species only lists those insects (adults, larvae or juveniles) occurring in the eulittoral zone, in the tidemark or in washed ashore organic material are listed below. This information is based on recent literature, compiled by Belgian experts in the field of entomology. Insects living higher up on the beach and in the dunes are not yet included.

Number of groups undocumented in BeRMS (2010-08-25)

For a number of taxonomic groups, no species were documented (sofar) in the Belgian part of the North Sea. Known shortcomings and additions can be communicated with VLIZ, so the list can be updated.

For the following groups, literature was searched without results:

  • Acanthocephala
  • Acarina
  • Anaspidacea
  • Bathynellacea
  • Branchiura
  • Cephalocarida
  • Ganthostomulida
  • Hemichordata
  • Mesozoa
  • Mystacocarida
  • Nematomorpha
  • Pentastomida
  • Placozoa
  • Priapulida
  • Remipedia
  • Staurozoa
  • Stomatopoda
  • Tantulocarida
  • Tardigrada
  • Thermosbaenaceae