Parasitic worms or Helminths display immense biodiversity. They include agents that cause many parasitic diseases in humans and animals.


Presentation
The Helminth collection includes the two main branches of parasitic worms: Nematodes (roundworms) and Platyhelminthes (flatworms). For the Platyhelminthes, the collection comprises representatives of the three main groups: Digenea, Cestodes and Monogenea. As well as these main branches, the collection includes Nematomorpha (or Gordian worms), Acanthocephala, Leeches and various very small groups of parasites. All these animals are parasites of Vertebrates and sometimes Invertebrates. Some of these parasites are parasites of humans or domestic animals, and are responsible for European or tropical parasitic diseases (helminthiasis, filariasis, bilharziosis). The Nematodes are generally preserved in alcohol, in tiny glass bottles. The large Cestodes are in glass jars. Many parasites are preserved between a slide and a cover slide. These slides have two labels, one for the host name, another for the parasite name. The collection thus contains over 40,000 lots (one lot can contain between one and a hundred or so individuals), including over 1,000 holotypes and paratypes.

History
The Parasitic Worm collection was mainly assembled between 1950 and 1990 based on material harvested by members of the former Laboratoire des Vers directed by Professor Alain Chabaud, on missions all over the world. The collection already contained a large historical archive. However, it has expanded more recently with donations from famous French helminthologists like Yves-Jean Golvan (Acanthocephala collections). The modern 21st-century collections include recent fish parasite harvests from New Caledonia by Jean-Lou Justine. Another recent addition is Professor Louis Euzet’s immense collection of fish parasites, Monogenea and Cestodes.

Research
The research areas relating to the collection are systematics and of course human, veterinary and general parasitology. The collections are visited by researchers from various countries who come to compare their specimens to the type specimens. These researchers also deposit specimens of their new species so that future generations can access the material on which they have worked. Every host animal species has at least one parasite species associated with it, often more. Therefore, there are more parasite species than host animal species. Despite their large numbers, the Parasitic Worm collections only account for a small part of parasite biodiversity, and are likely to grow.