Several species of avian schistosomes are known to cause dermatitis in humans worldwide. In Europe, this applies above all to species of the genus Trichobilharzia. For Austria, a lot of data are available on cercarial dermatitis and on the occurrence of Trichobilharzia, yet species identification of trematodes in most cases is doubtful due to the challenging morphological determination of cercariae. During a survey of trematodes in freshwater snails, we were able to detect a species in the snail Physella acuta (Draparnaud, 1805) hitherto unknown for Austria, Trichobilharzia physellae; this is also the first time this species has been reported in Europe. Species identification was performed by integrative taxonomy combining morphological investigations with molecular genetic analyses. The results show a very close relationship between the parasite found in Austria and North American specimens (similarity found in CO1 ≥99.57%). Therefore, a recent introduction of T. physellae into Europe can be assumed.

We designed and tested species-specific PCR primers to detect Trichobilharzia species via environmental DNA (eDNA) barcoding in selected Austrian water bodies. Tests were performed with eDNA samples from the field as well as with artificial samples from the lab, where snails releasing cercariae were kept in aquariums. From two localities, Trichobilharzia was documented based on the release of cercariae from snails, enabling morphological species identification. In both cases, the corresponding species were detected via eDNA: Trichobilharzia szidati and Trichobilharzia physellae. Nonetheless, the stochasticity was high in the replicates. PCR tests with aquarium water into which the cercariae had been released allowed eDNA detection even after 44 days. As in the PCRs with eDNA samples from the field, positive results of these experiments were not obtained for all samples and replicates. PCR sensitivity tests with dilution series of T. szidati genomic DNA as well as of PCR amplification products yielded successful amplification down to concentrations of 0.83 pg/µL and 0.008 pg/µL, respectively. Our results indicate that the presumed species specificity of PCR primers may not be guaranteed, even if primers were designed for specific species. This entails misidentification risks, particularly in areas with incomplete species inventories.

Many aquatic habitats have become vulnerable to rapid and long-term changes induced by industrialism, air pollution, tourism, fishing activities etc. These factors created an urgent need for extensive water monitoring and conservation. By observing the behaviour of lifeforms, we can monitor the state of the environment. Here, we present the methodology, calibration approaches and preliminary results of designing a biohybrid entity for aquatic monitoring. Biohybrid robots combine mechanical and electronic elements with living organisms or tissues. This biohybrid consists of several modules, each hosting or attracting different species and communities. We focus on animals such as Daphnia sp., zebra mussel Dreissena polymorpha and various representatives of the plankton community. The first results showed that 1) both Daphnia and D. polymorpha show no clear signs of confinement-induced stress, 2) the designed structures are examples of suitable tools for hosting the organisms, observing their behaviour and collecting and storing data and 3) their behaviour can be calibrated under laboratory conditions to be able to extrapolate the field data into environmental data.