FIRST RECORDS OF BAT PARASITES IN KARELIA

First data on parasites from bats (Chiroptera) in Karelia are presented. Bats were captured at hibernacula in Lahdenpohsky and Sortavalsky Districts of Karelia in March 2010 and February 2011. Partial helminthological dissection was applied to 12 bat individuals of three species: northern bat Eptesicus nilssonii Keyserling & Blasius, 1839 (8 specimens), brown long-eared bat Plecotus auritus (Linnaeus, 1758) (1 spm.), and Brandt’s bat Myotis brandtii (Eversmann, 1845) (3spm.). Ectoparasites were collected from the bats captured in March 2010: E. nilssonii – 6 individuals (3 from each of Sortavalsky and Lahdenpohsky Districts), P. auritus – 1 ind. (Lahdenpohsky District), M. brandtii – 1 ind. (Sortavalsky District). The surveys revealed 14 species of parasites from different taxonomic groups. All the parasites were found in Karelia for the first time. Helminthes were represented only by trematodes of 3 families: Plagiorchiidae (Plagiorchis vespertilionis, P. koreanus, P. muelleri), Lecithodendriidae (Lecithodendrium linstowi, Paralecithodendrium chilostomum, P. skrjabini), and Pleurogenidae (Parabascus magnitestis). Ectoparasites in the samples include gamasid mites of the families Spinturnicidae (Spinturnix kolenatii, S. plecotinus) and Macronyssidae (Macronyssus crosbyi, M. cyclaspis), chigger mites of the family Trombiculidae (Leptotrombidium sp.), and fleas of the family Ischnopsyllidae (Ischnopsyllus hexactenus, Ischnopsyllus sp.). All the parasites are bat specialists, known to occur in various parts of Russia and Europe.

Chiropterans of Karelia have been addressed by few papers, focused on the distribution boundaries, species composition and abundances [Belkin et al., 2015[Belkin et al., , 2019. Some publications deal with the study of various aspects of the physiological state of hibernating bats in Karelia [Ilyukha et al., 2015;Kizhina et al., 2018;Uzenbaeva et al., 2019]. There are no data on bat parasites in the territory of Karelia.

Material and methods
Bats were captured at hibernacula in Lahdenpohsky (61°32ʹN, 30°12ʹE) and Sortavalsky (61°57ʹN, 30°35ʹE) Districts of Karelia in March 2010 and February 2011. The hibernacula were not natural habitats, but man-made caves and lined underground spaces. The conditions in the Ruskeala adit (Sortavalsky District), in comparison with the concrete tunnel in the Lahdenpohsky District, were characterized by lower temperature and high relative humidity due to year-round water pooling [Belkin et al., 2015].
Ectoparasites were collected from the bats cap- Parasite identification relied on keys: Medvedev, 1996;Stanyukovich, 1997;Kudryashova, 1998;Tkach et al., 2000;Kirillov et al., 2012;Orlova et al., 2015. The following parameters were used to quantify the bats' infection rate: (Ab) Average infection intensity (number of parasites per 1 host specimen) or Abundance: Ab = Σn/N, where N is the number of examined bats and Σn is the total number of parasites found in all examined bats; Minimum and maximum number of parasites registered in the host.
were represented only by trematodes belonging to 3 families: Plagiorchiidae, Lecithodendriidae, and Pleurogenidae. Ectoparasites in the samples included gamasid mites of the families Spinturnicidae and Macronyssidae, chigger mites (Trombiculidae), and fleas of the family Ischnopsyllidae.

Trematoda
Family Plagiorchiidae Lühe, 1901 Genus Plagiorchis Lühe, 1899 Plagiorchis vespertilionis (Müller, 1780) Found in all the 3 host species. The infection rate was the highest in the northern bat: 7 of the 8 host individuals were infected (Ab 11; 7-24); two of the three M. brandtii were infected (Ab 14; 7-21); the only examined P. auritus specimen contained two trematodes. It is a widespread parasite of bats [Kirillov et al., 2012]. The species was encountered in Karelia for the first time.
Plagiorchis koreanus (Ogata, 1938) Singular specimens were retrieved from all the three host species: one of the 8 captured E. nilssonii hosted one worm, M. brandtii and P. auritus each hosted 2 worms. It is a widespread parasite of bats [Kirillov et al., 2012]. The species was encountered in Karelia for the first time.
Plagiorchis muelleri Tkach et Sharpilo, 1990 Trematodes were retrieved only from P. auritus (one worm) and M. brandtii (two worms). It is a widespread parasite of bats [Kirillov et al., 2012]. The species was encountered in Karelia for the first time.
Family Lecithodendriidae (Lühe, 1901) Genus Lecithodendrium Lühe, 1896 Lecithodendrium linstowi Dollfus, 1931 In Karelia this species was found only in the northern bat. Five of the eight host individuals were infected, and the intensity of infection ranged from 2 to 260 worms (Ab 35). The life cycle of this parasite most probably involves semi-aquatic flying insects on which bats feed actively late in summer and in autumn. Flukes mature soon after infesting the host and overwinter this way. Almost all the retrieved individuals were mature, and the uterus of the worms was fully packed with eggs. A similar situation was observed for Prosthodendrium longiforme (Bhalerao, 1926) in Myotis daubentonii and M. brandtii from the Samara Region [Kirillova, Kirillov, 2012]. It is a widespread parasite of bats [Kirillov et al., 2012]. The species was encountered in Karelia for the first time.

Genus Paralecithodendrium Odhner, 1911
Paralecithodendrium chilostomum (Mehlis, 1831) The species was found only in the northern bat. Five of the eight host individuals were infected (Ab 81; 3-347). This species demonstrated the same pattern as Lecithodendrium linstowi, i. e. only mature individuals were present, with the uterus packed with eggs. It is a widespread parasite of bats [Kirillov et al., 2012]. The species was encountered in Karelia for the first time.
Paralecithodendrium skrjabini Schadybin in Skarbilovich, 1948 Only two worms were found in one northern bat individual. The species is a bat specialist. Previously known in Russia only from the Chita, Nizhny Novgorod and Samara Regions [Kirillov et al., 2012]. The species was encountered in Karelia for the first time.

Family Pleurogenidae Looss, 1899 Genus Parabascus Looss, 1907
Parabascus magnitestis Khotenovski, 1985 Three specimens of the parasite were retrieved from one Brandt's bat. The species is a bat specialist. Previously known in Russia only from the Voronezh and Samara Regions [Kirillov et al., 2012]. The species was encountered in Karelia for the first time.
Ischnopsyllus sp. Two females were collected from M. brandtii from the Sortavalsky District. One of the two individuals had only seven combs of ctenidia; the 3 rd comb was absent. The collected fleas are similar to the species Ischnopsyllus simplex Rothschild, 1906 andI. mysticus Jourdan, 1942, the females of which do not differ in morphology [Medvedev, 1996]. These species are common in the Palaearctic Northwest. In Estonia and Finland, these species have also been observed in the Brandt's bat [Medvedev, Mazing, 1987;Virta, 2014].
In the northern bat (E. nilssonii), 10 species of parasites were found. Five of them were trematodes. The parasite Plagiorchis vespertilionis occurred in the greatest number of host species, while helminths of the species Lecithodendrium linstowi and Paralecithodendrium chilostomum were the most abundant. Ectoparasites in the sam-ples were represented by mites Spinturnix kolenatii, Macronyssus crosbyi and M. cyclaspis, larvae of chigger mites Leptotrombidium sp., and the flea Ischnopsyllus hexactenus. The diversity of the parasite fauna in the northern bat is probably explained by the highest number of host individuals examined.
Being insectivorous, bats are infested by all trematode species while feeding on infected flying insects. All the trematode species detected in our study are bat specialists, known to occur in various parts of Russia and Europe [Kirillov et al., 2012].
Thus, our surveys have yielded only the first records of bat parasites in Karelia. More sampling is needed to expand our knowledge of the parasite species composition of this host group.