Parasitic helminths are invertebrate animals from various taxa, e.g. round worms (Nematoda), spiny-headed worms (Acanthocephala), tape worms (Cestoda), monogenean and parasitic flukes (Trematoda). They are endoparasites and live within their host in various locations. Most species parasitize the intestine; however, virtually every inner organ can be colonized by helminths, depending on their specialization (liver: liver fluke; lung: lung worms; lymphatic organs, blood, skin: various filarioid nematodes). Beside their preferences for specific organs, parasitic worms also have a distinct host preference. Some helminths have a broad host range, whereas others are only able to parasitize a single host species. Most helminthes are highly adapted and long-living. Due to their ubiquitous distribution and the large number of species their importance as pathogens should not be underestimated.

Although there is a sound knowledge about parasitic worms of humans, some pets and livestock there is a lack of information about parasitic helminths in Austrian wild animals. In addition, many helminth species have only few morphological characteristics and are therefore difficult to determine to the species level, or can only be specified in certain life-cycle stages. For these cases, molecular barcoding technology is also of immediate practical importance.

In the ABOL pilot project, standard protocols for the collection of morphological and genetic data for helminths were established. COI primers for the helminth groups Nematoda (excluding Filarioidea), Filarioidea (filarioid nematodes), Neodermata (Cestoda, Trematoda and Monogenea) and Acanthocephala were developed and tested on individuals from the scientific collections of the NHMW and the Vetmeduni Vienna. Further samples from offal collected from birds, small mammals, wild boars, and fish from the ABOL pilot project “Barcoding of native wildlife” were included. A total of 427 samples were analysed, of which 251 were successfully sequenced. For more than half of these individuals morphological determination at species level was also possible. As there were only 8 barcodes of Austrian helminths on BOLD before the project, the obtained barcodes are an important basis for future projects.