Acanthocephalans are intestinal parasites of fish that use amphipods as their intermediate host. In the UK, greatest attention has been given to Pomphorhynchus laevis, which matures in freshwater fish such as chub and barbel, and cycles through Gammarus pulex. Recent taxonomic studies have suggested there are two closely related species of Pomphorhynchus, P. laevis and P. tereticollis. This has raised uncertainty over the identity, distribution and impact of these parasites in our rivers. Further studies are needed to clarify the status of this parasite in the UK to improve understanding of parasite diversity and underpin regulatory controls to protect wild fish populations. Click HERE for more information and to see how ARMI volunteers can get involved.