Helminth fauna of insectivorous mammals (Mammalia: Soricomorpha, Erinaceomorpha) in the National Park “Smolny” (Republic of Mordovia)

In 2018-2021 on the territory of the National Park “Smolny”, the helminth fauna of five species of insectivores was studied for the first time. In total, 31 species of parasitic worms were recorded: 6 cestodes, 8 trematodes, 16 nematodes and one acanthocephalan. The species composition of parasites is richest in Sorex araneus (22 species). The helminth fauna of Erinaceus roumanicus (8), Neomys fodiens (5) and Sorex minutus (4) is less diverse. The smallest number of helminths was observed in Talpa europaea (2 species). The species diversity of the helminths in species of insectivores is determined by the width of the ecological niche that the animal occupies in the biocenosis. The most diverse and rich composition of helminths is possessed by the most widespread and eurybiont species - the common shrew. The nematodes Aonchotheca exigua and Pseudophysaloptera soricina were recorded for Neomys fodiens in Russia for the first time. The trematodes Rubenstrema opisthovitellinus, Strigea strigis, mtc. and cestode Dilepis undula, larvae were recorded for the first time in S. araneus in the Volga basin. Sorex araneus is a new host for the nematode Hadjelia truncata, juv. Most parasite species (22) found in insectivorous mammals have a Palearctic distribution. Of the 31 species of helminths noted in insectivores, only one species (the nematode Physocephalus sexalatus) has medical and veterinary significance as a potential causative agent of dangerous helminthiasis.