Deep in 2022, we promised to publish the numbers collected by the European Xiphophorus census, after they undergo the necessary editing and “cleansing” of obvious errors. In the end, it took us a long time and the search for the origins of individual strains is not over. But we’re not going to wait for the “perfect product” anymore, and we’re going to post what we have. After all, these are data from you, Xiphophorus breeders from various European countries.

If you do not know the basic information about how the census was conducted and what data we obtained from it, please read the original article here.

Note that (for the purpose of this summary) we have grouped strains originating from the same locality, but e.g. from different collection years or different spots along the same river. We have removed additional data (such as names, dates, GPS etc.), so the result is only individual strains by locality that we might consider to be genetically identical. This in no way means that fish from different locations are genetically different, but we don’t want to get into that now; some separate strains that are genetically or geographically identical to others still remain listed (we have not yet pinpointed some locations). Some species also have “strains” that are selectively bred, or we can doubt their origin very much, because it is indicated very generally. Typical examples are Xiphophorus hellerii or X. maculatus. We’re leaving them on the list for now. On the contrary, for species where only one locality is known (albeit extensive), we grouped the strains under a single label.

The PDF summary of our census can be downloaded here:

What’s next?

In the original article, you will find not only summary statistics and evaluation, but also several questions that Kees raised. Let’s repeat them here:

  • Are we going to propose a way to describe the location? I know this has been a subject for discussions many times already.
  • How far do we want to go with exchanging fish? Are we going to use ESU’s like the GWG does?
  • Should we try to get more breeders for some of the species that are only maintained by a few people? These are also the species that have a small habitat and might be considered at least vulnerable. Maybe we can do it in the same way as in the Northern Platyfish project? Who is going to do it?
  • It would be helpful if we could get a kind of HQ in Mexico like the GWG have with the university of Morelia. Is there a possibility to do this? How important it is?
  • Fresh blood is a very often mentioned subject. Are we going to have more controlled exchange of fish between breeders and is this useful? Having a look at the colours of a platy strain in nature and the same strain 10 years later in the aquarium, it makes it clear that we are losing traits from the original strains. Introducing wild fish to an aquarium strain is not a good idea. You should keep the new fish separated. Should we get more wild strains or stick with what we have and exchange these?

Well, we have already started working on answering the question about the “Mexican base” this year – see the article on the Mexico 2023 project. It’s far from solved, but we’re working on it.

All other questions await active XWG members, species coordinators. They will work with complete census results including all details. Their task is to put together and clean the data and, above all, to work with individual breeders to ensure that we do not lose any strains from European aquariums. It is our common interest and everyone can get involved – either as a breeder or as a coordinator for a certain species. You can find more about our organization here.