Prevalence and molecular identification of the sinus worm Skrjabingylus petrowi (Nematoda: Metastrongyloidea) from Martes spp. in Germany

The nematodes of the genus Skrjabingylus (family Metastrongylidae) can parasitise the nasal and frontal sinus cavities of different carnivore species. Until recently, Skrjabingylus petrowi Bageanov & Petrov, 1941, has mainly been described in pine martens (Martes martes Linnaeus, 1758) and sables (Martes zibellina Linnaeus, 1758) sampled in the European part of the former Soviet Union. Newer finds in the stone marten (Martes foina Erxleben, 1777) and from different parts of Europe suggest, however, that the species might have a broader host-species range than previously assumed and be geographically more widespread as well. Since most S. petrowi records have resulted from chance discoveries rather than systematic surveys, very little is known about the prevalence of S. petrowi in marten populations. Here, we report results of a 20-year extensive survey of fresh marten skulls, where we tested 1.059 marten carcasses originating from 248 localities in Germany for the presence of S. petrowi. We identified an infestation in only four M. martes individuals and one M. foina, despite using a reliable identification method. Based on the spicule lengths of the male nematodes, the parasites were identified as S. petrowi and genetic barcoding confirmed the identification of the samples. In a phylogenetic analysis, S. petrowi and Skrjabingylus nasicola (Leuckart, 1842), formed a sister clade to all the other members of the family Metastrongylidae. The low prevalence of S. petrowi is possibly due to its parasitising in the two marten species that are either not very common (M. martes) or predominantly live in urban habitat (M. foina).