Anisakidae nematodes in capelin Mallotus villosus (Müller, 1776) (Actinopterygii: Osmeridae) caught for food purposes

Capelin Mallotus villosus, a representative of the Osmeridae, is a common species found in the North Atlantic, Pacific and Arctic Ocean. Being one of the main components of the diet of various fish species, it plays an important role in the circulation of different parasite species, including the nematodes of the Anisakidae. Capelin is also extensively caught and used for human food, and has become increasingly available to consumers in Poland. Thirty six capelin specimens, smoked fish bought at a store in Gdynia, were examined for the presence of Anisakidae. Ten specimens of nematode (Anisakis simplex, Contracaecum sp.) were found in eight fish. The overall prevalence for the fish was 22.2%, with a mean intensity of 1.3 (range 1-3). Despite its widespread acquisition and use, capelin has been the subject of few parasitological analyses. Our findings indicate that it is a typical host of Anisakidae nematodes, a species of great zoonotic importance. While dead nematode specimens found in smoked fish do not pose a direct threat to humans as parasites per se, they can cause food allergies. It seems, therefore, that fish intended for consumption should be the subject of constant parasitological monitoring, linked to food quality control.

A New Species of Demodex (Acariformes: Prostigmata) Observed in the Mouflon, Ovis aries musimon (Artiodactyla: Bovidae) with Data on the Parasitism and Occurrence of Other Ectoparasites

A greater understanding of mite biodiversity and ecology can explain their preference for microhabitats within host bodies, i.e., as ecto-, meso-, and endoparasites. Similarly, learning about the patterns formed by mite communities in wild animals can shed light on the mechanisms of parasitosis development in their domesticated counterparts. Hence, the present study examined the acarofauna of the mouflon, introduced to Poland in the early 20th century from a region of endemic occurrence. Forty-one individuals were examined for the presence of ectoparasites between 2010 and 2013; later, skin fragments were analysed for the presence of skin mites. A new species of Demodecidae, Demodex musimonis sp. nov., was discovered in the skin of the pasterns of 14.6% mouflons, as well as the ectoparasitic tick Ixodes ricinus (prevalence 29.3%) and ungulate-typical fly Lipoptena cervi (34.1%). However, no mites typical for ovine Ovis (Psorergatidae, Psoroptidae) were noted, nor any colonisation of microhabitats by species from local ungulates, resulting from the loss of original parasites during the introduction. A comparison of the acarofauna of the mouflon and domestic sheep Ovis aries aries suggests that a mite community with a complex structure and the co-occurrence of different families may be formed. However, it is not known whether the acarofauna of domestic sheep is derived from wild ancestors or the process of domestication. Even so, the peculiar Demodecidae must have been part of the natural parasitofauna of wild sheep, of which only D. musimonis sp. nov. has been recognised so far.

Demodex murilegi and Demodex obliquus, two new specific skin mites from domestic cat Felis catus, with notes on parasitism

The Demodecidae are skin and tissue parasites of mammals with high host, topical, and topographic specificity. They may cause a demodecosis, typically observed in pets and humans. Numerous mammal species have been found to have several, specific demodecids, which inhabit different microhabitats. Thus far, two species have been known from the domestic cat, namely Demodex cati Megnin, 1877 (Acariformes: Demodecidae) and D. gatoi Desch and Stewart, 1999; however, there have been indications for the presence of other demodecid mites in this host. Presently, two other species are described, D. murilegi sp. nov. associated primarily with the skin from the area of lips and nose, and D. obliquus sp. nov. associated with the skin of the lower part of the limb. They exhibit morphological discreteness in terms of qualitative traits significant for Demodecidae taxonomy. Demodex murilegi sp. nov. is larger than both known species, and D. obliquus sp. nov. is intermediate in length between them. It is likely that infection with different Demodex species may result in variable symptoms and courses of demodecosis; however, a correct identification of the species causing the parasitosis is needed to confirm this. Thus, the present study compares the taxonomic traits of four cat demodecid mites.

Demodex bialoviensis sp. nov. (Acariformes, Demodecidae) a new, specific parasite of the European bison Bison bonasus (Artiodactyla, Bovidae)

Sixteen species of parasitic mites of the family Demodecidae have been described in ungulates (Ungulatomorpha), particularly among domestic animals and livestock. Specific synhospital species have been found in seven host species. Demodex bisonianus, occurring in the Meibomian glands of the eyelids, was described in the European bison Bison bonasus. Together with Trypanosoma wrublewskii and Bisonicola sedecimdecembrii, it is one of the three known specific parasite species of European bison. The European bison is not only a rare and endangered mammal, but its biology has been shaped by its recent restitution from extinction from a small pool of individuals kept in breeding facilities. This could have been the reason for the extinction of the majority of specific parasites. The present study reports the finding of a new specific parasite species, Demodex bialoviensis sp. nov., associated with the nasal skin region, in European bison from the Białowieża Forest (Poland). It is the second species of Demodex reported in this host species, however occurring in a different location.

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The European bison is the largest European land mammal; despite its successful restitution, remains highly endangered.

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Only three specific parasite species have been known in the European bison, including one mite – Demodex bisonianus.

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Currently, another representative of Demodecidae, Demodex bialoviensis sp. nov. has been found in the European bison.

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Demodex. bisonianus occurs only in the area of the eyelids, and D. bialoviensis sp. nov. in the nasal skin region.

Demodex crocidurae, a New Demodecid Mite (Acariformes: Prostigmata) Parasitizing the Lesser White-Toothed Shrew and a Redescription of Demodex talpae from European Mole with Data on Parasitism in Soricomorpha

Simple Summary

This paper describes a new species, Demodex crocidurae, inhabiting the hairy skin of Crocidura suaveolens. It also redescribes the most morphologically similar form: Demodex talpae from Talpa europaea, a species known from Hirst’s 1921 description. Following a differential diagnosis, it was concluded that these are separate species with different features important in the taxonomy of Demodecidae, inhabiting analogous microhabitats in different species of hosts.

Abstract

Only six parasitic species of Demodecidae mite have thus far been described from the Soricomorpha, these being associated with the common shrew Sorex araneus Linnaeus, 1758, and the Mediterranean water shrew Neomys anomalus Cabrera, 1907 (two species from each host), and with the lesser white-toothed shrew Crocidura suaveolens (Pallas, 1811) and the European mole Talpa europaea Linnaeus, 1758 (one from each host species). Presently, Demodex crocidurae, a new species, has been described from the territory of Poland for C. suaveolens; in order to confirm its validity, it was necessary to redescribe D. talpae Hirst, 1921, from T. europaea, a demodecid species first described by Hirst in 1921 from England and then noted only in Poland. Both species colonized the hairy skin of the body in their hosts, where no disease symptoms of infestation were observed. However, D. crocidurae showed higher infection parameters (prevalence 100%, mean intensity 11.7, intensity range 3–26 individuals) than those of D. talpae (30.0%, 4.7, 2.0–8.0), possibly due to different host biology.

A global checklist of the parasites of the harbor porpoise Phocoena phocoena, a critically-endangered species, including new findings from the Baltic Sea

The common harbor porpoise is a widely-distributed marine mammal with three known subspecies, including P. phocoena phocoena, with a clearly distinct and critically endangered (CR) subpopulation from the Baltic Sea (Baltic Proper). As part of an assessment of the condition and health threats of these mammals, it is important to conduct parasitological monitoring. The aim of the study was therefore to compare the data on porpoise parasitofauna from this subpopulation with those on porpoises from other areas. The study included 37 individuals from 1995 to 2019; eight species of parasites were found (prevalence 83.8%, mean intensity 724.2, range 2-3940), with a predominance of lung nematodes - Stenurus minor (94.7%), Torynurus convolutus (69.4%), Pseudalius inflexus (63.8%), Halocercus invaginatus (22.2%); the highest intensity was recorded for S. minor (989, 53-2928). Two species of Anisakidae (Anisakis simplex - 33.3%, Contracaecum sp. - 20.0%) were found in the digestive tracts, which were a new record for this population. The fluke Campula oblonga was found in the livers of 31.3% of porpoises. The tapeworm Diphylobothrium stemmacephalum was also recorded in the intestine of one individual; this is typical for these hosts, but previously undetected in the Baltic subpopulation. Parasites coexisted in numerous hosts, constituting a heavy burden for them. The obtained data were compared with those from the P. phocoena parasitofauna from other regions, based on a compiled checklist (1809-2021) including all species of porpoise parasites (55 taxa). Compared to the worldwide porpoise parasitofauna checklist, the number of parasites found in the nominative subspecies (Baltic Proper subpopulation) is small: including only 10 taxa (eight in the current study). These species are typical of porpoises and usually the most common; however, the level of infection of Baltic porpoises (intensity and total parasite load) is very high, which can undoubtedly have a negative impact on their condition and overall health.

The first description of the nymphal stages of Hoplopleura longula (Psocodea: Anoplura: Hoplopleuridae) from the harvest mouse Micromys minutus (Rodentia: Muridae)

Background

Despite the widespread belief that an extensive body of knowledge exists for the sucking lice (Anoplura), some of their common, Eurasian or even cosmopolitan species still lack complete taxonomic descriptions, especially those for their nymphal stages. This applies especially to the most common rodent parasites: the lice of the genus Hoplopleura. In Europe, only two of the five most common Hoplopleura species have full taxonomic characteristics with a description of the nymphal stages. This study enriches the current state of knowledge for another species, Hoplopleuralongula and presents the first description of its nymphal stages.

The study includes five rare louse specimens (two nymphs I, one nymph II, two nymphs III) of H.longula collected from 63 Eurasian harvest mice Micromysminutus. The collected lice were fixed and preserved in 70% ethyl alcohol solution and then placed in polyvinyl-lactophenol to form total preparations.

New information

Only two of the five species found in Eurasia (H.acanthopus, H.affinis, H.captiosa, H.edentula and H.longula) have been given full taxonomic descriptions, including immature stages. This paper presents a description of the nymphal stages of H.longula (described for the first time).

Morphological anomalies in the body structure of Hoplopleura spp. (Anoplura: Hoplopleuridae)

Morphological anomalies in sucking lice (Phthiraptera: Anoplura) have been discussed sporadically, mainly when the changes were considerable, such as in the structure of the reproductive organs or pleural plates, and have concerned the most commonly-studied species. An analysis of 376 specimens from three species of the genus Hoplopleura (H. acanthopus, H. affinis, H. edentula) identified 13 individuals with changes in the number and size of the setae on the sternal plates of the abdomen and irregularities in the structure of the plate itself (3.5% of the collection). The above anomalies do not invalidate the taxonomic decisions.

Anisakid nematodes in dolphins (Cetacea: Delphinidae) from the Baltic Sea area

Dolphins are rarely observed in the Baltic Sea, making only sporadic appearances as a result of their migrations. The study included six specimens: four white-beaked dolphins Lagenorhynchus albirostris and two striped dolphins Stenella coeruleoalba. Their gastrointestinal tracts were found to contain the nematodes Anisakis simplex (in both species) and Contracaecum sp. (only in the white-beaked dolphins). This is the first record of Anisakidae nematodes in dolphins found in the Baltic Sea.

Checklist of the parasites of European eel Anguilla anguilla (Linnaeus, 1758) (Anguillidae) in Poland

The present paper lists all parasite species of the European eel Anguillaanguilla (Linnaeus, 1758), recorded in Poland, in both its saltwater and freshwater habitats. The list has been drawn up, based on data acquired since 1844. The majority of included parasite species are presented with fish infection parameters together with data on their developmental stages and occupied microhabitats, localities and dates of collection of the eels themselves. The database includes 62 parasite taxa (including 50 species, nine identified to the genus level and three to higher taxa), representing at least 47 genera and 39 families. The most frequently-noted parasites of the European eel are the cestode Bothriocephalusclaviceps, the nematodes Anguillicoloidescrassus, Camallanuslacustris and Raphidascarisacus and the acanthocephalan Acanthocephaluslucii. Four alien species have been noted from this host: A.crassus, the monogeneans Pseudodactylogyrusanguillae and Pseudodactylogyrusbini and the acanthocephalan Paratenuisentisambiguus. The present list includes both new host records and earlier records not included in previous lists of parasites of eels.

The helminthofauna of the garfish Belone belone (Linnaeus, 1760) from the southern Baltic Sea, including new data

The garfish Belone belone (Linnaeus, 1760) is a marine fish which can be found in the shallow waters of the Baltic Sea in the spring and summer spawning period. In 2010 and in 2016, 73 specimens of garfish collected in the Gulf of Gdansk (southern Baltic Sea) were examined for the presence of helminths. The fish were found to support the nematode Anisakis simplex (Rudolphi, 1809) L3, Hysterothylacium aduncum (Rudolphi, 1802) L4, ad., Contracaecum sp. L3 as well as the acanthocephalan Echinorhynchus gadi Zoega in Müller, 1776. For all garfish caught in 2010 and 2016, the overall prevalence of infection by all parasites was 38.4%, with a mean intensity of 2.9 (range 1-5). The dominant parasites were H. aduncum (20.5%, 1.8) and E. gadi (17.8%, 2.1). This study constitutes the first record of Contracaecum larvae in garfish in the Polish exclusive economic zone of the Baltic Sea.

Digenetic trematode Ogmogaster antarcticus (Notocotylidae) in a fin whale Balaenoptera physalus (Balaenopteridae) stranded in the Baltic Sea

On 28 August 2015, a dead fin whale Balaenoptera physalus (Linnaeus, 1758) was collected from the waters of the Gulf of Gdan΄%%KERN_ERR%%sk (Baltic Sea). The individual was a male in a poor nutritional condition with an empty stomach. Over 34000 Ogmogaster antarcticus flukes were found in the colon and rectum. This is the first observation of O. antarcticus in the Baltic Sea.

Demodex foveolator (Acariformes: Demodecidae) from Crocidura suaveolens (Soricomorpha: Soricidae) – the second observation worldwide, and a checklist of the demodecid mites of soricomorphs

Thus far, only six species of parasitic mites of the Demodecidae family have been recorded in hosts from the Soricomorpha: two from the common shrew (Sorex araneus), two from the Mediterranean water shrew (Neomys anomalus), one from the lesser white-toothed shrew (Crocidura suaveolens) and one from the European mole (Talpa europaea). The present study describes the identification of Demodex foveolator in C. suaveolens from the area of Poland (the Wielkopolska region). This is only the second record of this species in the world, a new mite species for the Polish fauna and a new host record in Poland, i.e. the first identification of Demodecidae in Crocidura mammals.

Demodex melesinus (Acariformes: Demodecidae) - the forgotten European badger parasite, rediscovered after 100 years

Among 15 demodecid mite species (Acariformes: Demodecidae) recorded from carnivorans Carnivora, 3 species were described from mustelids Mustelidae. They are known only from single records, for which Demodex erminae has been described from the stoat Mustela erminea from Great Britain and New Zealand, D. melesinus from the European badger Meles meles known solely from Great Britain and D. lutrae discovered in the Eurasian otter Lutra lutra from Poland. The current record confirms the existence of D. melesinus, in badger from Poland, after close to one hundred years from its original description, as well as the first detection of the male for this species.

The status of Demodex cornei: description of the species and developmental stages, and data on demodecid mites in the domestic dog Canis lupus familiaris

Demodecosis canina is one of the most important dog parasitoses, but its aetiology is still not well known. There are currently two known species of demodecid mite specific to the domestic dog Canis lupus familiaris Linnaeus, 1758 (Carnivora: Canidae). These are Demodex canis Leydig, 1859 (Acariformes: Demodecidae) and Demodex injai Desch & Hillier, 2003. There have also been many reports of the so-called 'short form', considered to be a separate species functioning under the name Demodex cornei nomen nudum, for which, however, no formal valid description has been documented. Taxonomic analysis of short forms of dog demodecid mites, associated with the stratum corneum, was performed, in line with the taxonomic criteria of Demodecidae systematics. This form was found to be a distinct species with features that differ from those of the other known species of this family. The species, including the adult and immature stages, is described. It is likely that different Demodex species parasitizing the domestic dog may be responsible for differentiated symptoms and different courses of demodecosis. However, the basis for clarifying this issue should be the correct, unambiguous identification of the species causing parasitosis.

Demodecid mites (Acariformes, Demodecidae) in brown longeared bat Plecotus auritus (Chiroptera, Vespertilionidae) – second record in the world and systematic status of Demodex chiropteralis Hirst, 1921

As many as 26 species of parasitic mites of the Demodecidae family have thus far been described in the Chiroptera, of which only three have been found in bats from Europe. The first of the latter group was Demodex chiropteralis Hirst, 1921, described on the basis of only two females originating from one bat from Great Britain; an observation which has never been made since. The present study reports the discovery of both male and female D. chiropteralis in Poland, together with other unknown demodecid mites which may well belong to new species. The present study confirms the existence of D. chiropteralis after nearly one hundred years from its original description, as well as the first determination of representatives of the Demodecidae in the Chiroptera of Central Europe.

Occurrence of ticks (Parasitiformes, Ixodida, Amblyommidae) on the skin of African buffalo Syncerus caffer (Sparrman, 1779) (Mammalia, Artiodactyla) originating from an area of the Republic of South Africa

Most ticks of the genus Amblyomma and Rhipicephalus are typical ectoparasites of bovine. However, information about survival in different environmental conditions or coexistence of different species is lacking. Amblyomma hebraeum Koch, 1844, Rhipicephalus appendiculatus Neumann, 1901 and R. maculatus Neumann, 1901 were found in the skin (fixed in the salt) of an African buffalo Syncerus caffer (Sparrman, 1779), brought to Poland from the Republic of South Africa. Most of the ticks were still alive during their collection.

New data on the distribution of Carios vespertilionis Latreille, 1802 (Ixodida, Argasidae) in bats (Chiroptera) from northern Poland

Carios vespertilionis Latreille, 1802 is a typical bat parasite, widely distributed in the Palearctic, Oriental and Afrotropical realms. Its localities were found throughout Poland, yet it is considerably more common in the south. Currently, 105 bats have been examined, collected in the period 1999–2017 from 27 localities in northern Poland; 102 C. vespertilionis larvae were noted in 6 bats of 3 species of the Pipistrellus genus, originating from 5 localities, of which all constitute new locality for the short-legged bat tick. Instances of C. vespertilionis larvae wintering in the hosts have been observed as well as occurrence of this parasite outside of bat breeding colonies.

Characterization of Demodex musculi Infestation, Associated Comorbidities, and Topographic Distribution in a Mouse Strain with Defective Adaptive Immunity

A colony of B6.Cg-Rag1tm1Mom Tyrp1B-w Tg(Tcra,Tcrb)9Rest (TRP1/TCR) mice presented with ocular lesions and ulcerative dermatitis. Histopathology, skin scrapes, and fur plucks confirmed the presence of Demodex spp. in all clinically affected and subclinical TRP1/TCR mice examined (n = 48). Pasteurella pneumotropica and Corynebacterium bovis, both opportunistic pathogens, were cultured from the ocular lesions and skin, respectively, and bacteria were observed microscopically in abscesses at various anatomic locations (including retroorbital sites, tympanic bullae, lymph nodes, and reproductive organs) as well as the affected epidermis. The mites were identified as Demodex musculi using the skin fragment digestion technique. Topographic analysis of the skin revealed mites in almost all areas of densely haired skin, indicating a generalized demodecosis. The percentage of infested follicles in 8- to 10-wk-old mice ranged from 0% to 21%, and the number of mites per millimeter of skin ranged from 0 to 3.7. The head, interscapular region, and middorsum had the highest proportions of infested follicles, ranging from 2.3% to 21.1% (median, 4.9%), 2.0% to 16.6% (8.1%), and 0% to 17% (7.6%), respectively. The pinnae and tail skin had few or no mites, with the proportion of follicles infested ranging from 0% to 3.3% (0%) and 0% to 1.4% (0%), respectively. The number of mites per millimeter was strongly correlated with the percentage of infested follicles. After administration of amoxicillin-impregnated feed (0.12%), suppurative infections were eliminated, and the incidence of ulcerative dermatitis was dramatically reduced. We hypothesize that the Rag1-null component of the genotype makes TRP1/TCR mice susceptible to various opportunistic infestations and infections, including Demodex mites, P. pneumotropica, and C. bovis. Therefore, Rag1-null mice may serve as a useful model to study human and canine demodecosis. D. musculi should be ruled out as a contributing factor in immunocompromised mouse strains with dermatologic manifestations.

Adult and Immature Stages of the New Species of the Genus Demodex (Acariformes: Demodecidae) with Data on Parasitism, Topography, and Topical Specificity of Demodecid Mites in the Yellow-Necked Mouse, Apodemus flavicollis (Rodentia: Muridae)

Demodex mollis n. sp. is described from the yellow-necked mouse, Apodemus flavicollis (Melchior, 1834), from Poland. It is a medium-sized demodecid mite (adult stages are, on average, 249 μm long) observed in the skin of the eyelid area. This new species is most similar to two other species occupying similar a microhabitat in hosts of the same genus-Demodex lacrimalis Lukoschus and Jongman, 1974 from Apodemus sylvaticus Linnaeus, 1758 and Demodex huttereri Mertens, Lukoschus and Nutting, 1983 from Apodemus agrarius (Pallas, 1771)-but it differs in the following features: the terminal palpi are equipped with 3 spines, including 1 large claw-like spine and 1 single spine; subgnathosomal setae (setae n) are situated on both sides of the anterior side of the pharyngeal bulb; claws on the leg tarsi are bifurcated and each is equipped with large subterminal spur and proximal pointed projection; the opisthosoma is soft and flexible; and the male aedeagus has a different shape and localization. The differences also relate to sexual dimorphism. Males are more robust and stocky, epimeral plates I and IV are connected at the midline part of the podosoma, and epimeral plates II and III are separated. Females are slender, epimeral plates I-III are connected at the midline of the podosoma, and epimeral plate IV ia fused in 1 plate. The new species was noted in 22.5% of mice, with a mean intensity of 7.0 parasites per host. The topography of demodecid mites was also analyzed in the skin of A. flavicollis, and also Demodex corniculatus Izdebska, 2012 was observed in the hairy skin of the bodies of all the examined mice.

A new genus and species of demodecid mites from the tongue of a house mouse Mus musculus: description of adult and immature stages with data on parasitism

The study of the parasitofauna of the house mouse Mus musculus (Rodentia: Muridae) Linnaeus is particularly important owing to its multiple relationships with humans - as a cosmopolitan, synanthropic rodent, bred for pets, food for other animals or laboratory animal. This article proposes and describes a new genus and species of the parasitic mite based on adult and immature stages from the house mouse. Glossicodex musculi gen. n., sp. n. is a medium-sized demodecid mite (adult stages on average 199 µm in length) found in mouse tissue of the tongue. It is characterized by two large, hooked claws on each tarsus of the legs; the legs are relatively massive, consisting of large, non-overlapping segments. The palps consist of three slender, clearly separated, relatively narrow segments, wherein their coxal segments are also quite narrow and spaced. Also, segments of the palps of larva and nymphs are clearly isolated, and on the terminal segment, trident claws that resemble legs' claws can be found. On the ventral side, in immature stages, triangular scuta, topped with sclerotized spur, can be also observed. Glossicodex musculi was noted in 10.8% of mice with a mean infection intensity of 2.2 parasites per host.

Demodex castoris sp. nov. (Acari: Demodecidae) parasitizing Castor fiber (Rodentia), and other parasitic arthropods associated with Castor spp

A new species of demodecid mite, Demodex castoris sp. nov. (Acari: Prostigmata: Demodecidae), is described based on adult stages from the skin of the nasal region of the Eurasian beaver Castor fiber Linnaeus, 1758, collected in Poland. This is the first detection of a representative demodecid mite in rodents of the suborder Castorimorpha and also represents the first detection of a skin mite in Eurasian beavers. The new species is a small skin mite (average 173 µm in length) characterized by sexual dimorphism related to body proportions. D. castoris sp. nov. was observed in 4 out of 6 beavers examined (66.6%), with a mean intensity of 10.8 and an intensity range of 2-23 ind. host(-1). This paper also contains a checklist of parasitic arthropods known from Castor spp.

Two New Species of Demodex (Acari: Demodecidae) with a Redescription of Demodex musculi and Data on Parasitism in Mus musculus (Rodentia: Muridae)

This article describes two new skin mite species found on the house mouse Mus musculus L., 1758. Demodex marculus sp. nov. is a very small demodecid mite (adult stages, on average, 99 µm in length) found in mouse skin in the abdomen, back, limbs, and anal area. It is characterized by relatively large bossing hammer-shaped supracoxal spines, embedded in the trapezoidal gnathosoma. Demodex fusiformis sp. nov., in turn, is a little larger (adult stages on average 111 µm in length), with a small oval gnathosoma equipped with fine, knob-like supracoxal spines. It was found in the skin of abdomen, back, and limbs. Moreover, Demodex musculi (Oudemans, 1897) was redescribed, which is small demodecid mite (adult stages on average 142 µm in length) and characterized by relatively large morphological variation and considerable sexual dimorphism. The characteristic feature of this species is the strongly elongated and rectangular gnathosoma equipped with very large wedge-shaped supracoxal spines. D. musculi was found in the skin of various, haired regions of the mice body (head, neck, abdomen, back, limbs, genital-anal region, and tail). Moreover, one more demodecid mite was found in the skin of the examined mice, it was Demodex flagellurus Bukva, 1985, which was found only in the genital area. Overall infection of Mus musculus L. by all species of Demodex was with the prevalence of 100%, mean intensity of 24.0, and range of intensity of 1-109. Despite high infection levels, no symptoms of parasitosis were observed in the hosts.

A new species of the genus Demodex Owen, 1843 (Acari: Demodecidae) from the ear canals of the house mouse Mus musculus L. (Rodentia: Muridae)

A new species Demodex conicus n. sp. is described based on adult and juvenile stages from the ear canals of the house mouse Mus musculus L. in Poland. The new species is most similar to D. auricularis Izdebska, Rolbiecki & Fryderyk, 2014 from the ear canals of the wood mouse Apodemus sylvaticus (L.), but differs in the following features: the gnathosoma is triangular, the supracoxal spines (setae elc.p) are conical, the spines on the terminal segment of palp are four, the striation on opisthosoma is fine but dense, the vulva is located at a distance of c.17 µm from posterior level of legs IV, and the male genital opening is located at the level of legs I. The differences also relate to body size and proportions, female D. conicus n. sp. being, on average slightly larger, and male significantly larger than D. auricularis. Males of the new species also have longer and more massive opisthosoma than males of D. auricularis. Demodex conicus n. sp. was found in 17.5% of the mice studied from different locations in Poland.

New data on occurrence of Demodex flagellurus (Acari, Demodecidae) - rarely recorded parasite from the house mouse Mus musculus (Rodentia, Muridae)

Demodex flagellurus Bukva, 1985 is one of two known demodecid mites of the house mouse Mus musculus Linnaeus, 1758, in which it is observed in genital area. Skin fragments of 30 house mice from various regions of Poland (residential buildings in Gdynia and Gdańsk, rural region in Wielkopolska-Kujawska Lowland) were examined. The mites were noted in 25.0% of the mice, with mean intensity of 48.0 and intensity range of 2-103. D. flagellurus demonstrated the differentiated occurrence in host populations.

New data on the prevalence of Trichodectes melis (Phthiraptera, Trichodectidae) on the European badger Meles meles (Carnivora, Mustelidae)

Trichodectes melis is a specific ectoparasite of the European badger Meles meles. Distribution of this chewing louse is little known, although presumably it coincides with the range of its typical host. In Poland, it has been found in only a few stands in the western part of the country. It has recently been observed in the area of the Białowieża Primeval Forest, where 81 specimens of T. melis (48 females, 7 males and 26 nymph forms) were collected from two female European badgers, mainly from the fur of the head area. No symptoms of infestation were observed.

A new species of Demodex (Acari: Demodecidae) with data on topical specificity and topography of demodectic mites in the striped field mouse Apodemus agrarius (Rodentia: Muridae)

This article describes morphological characteristics and the occurrence of Demodex gracilentus sp. nov., which was found in the striped field mouse Apodemus agrarius (Pallas, 1771) in the skin of vibrissae area. D. gracilentus occurred in 36.7% of the rodents examined. D. gracilentus is a relatively large representative of the genus (adult stages on average 292 microm in length), a slender, elongated body; characteristic feature of these mites are conical supracoxal spines on dorsal side of gnathosoma, palps with asymmetric, forked triple spines on palptarsus, and the presence of rhomboidal opisthosomal organ. So far, the occurrence of three specific representatives of the family Demodecidae has been demonstrated in A. agrarius: Demodex apodemi (Hirst, 1918) (= Demodex arvicolae apodemi Hirst, 1918), Demodex agrarii Bukva, 1994, and Demodex huttereri Mertens, Lukoschus et Nutting, 1983. The first one is related to common hair follicles, especially in the skin of the head, while the next one inhabits the external auditory meatus, and the last one occurs in the meibomian glands of the eyelids.

The occurrence of Demodex kutzeri Bukva, 1987 (Acari, Demodecidae) in red deer (Cervus elaphus L.) in Poland

The occurrence of Demodex kutzeri Bukva, 1987 was examined and compared in red deer coming from different populations--25 red deer from northern Poland (Masurian Lake District) and 25 from southern Poland (Lower Silesia). The total prevalence of infestation in red deer by D. kutzeri was 52% with the mean intensity of 38 individuals and the intensity range of 1-135. Parameters of infestation for red deer from northern Poland were much higher (68%, 49), while for other red deer--lower (36%, 16). Demodectic mites D. kutzeri are associated with common hair follicles, therefore they can be found in different parts of the body, however most of the specimens were found in the head skin. Regardless of the location and the infestation rate (including density of mites in the skin), infestations were not accompanied by symptoms of demodecosis.

Sarcoptic mites (Acari, Sarcoptidae) parasitizing the brown rat Rattus norvegicus (Berkenhout, 1769) (Rodentia, Muridae), with a new data for the fauna of Poland

One of the least researched groups of parasitic arthropods in the brown rat Rattus norvegicus (Berkenhout, 1769) are skin mites from the family of Sarcoptidae. Specimens representing two species of sarcoptic mites were found in 30 examined rats from northern Poland: Notoedres muris Megnin, 1877 and Trixacarus diversus Sellnick, 1944. The total prevalence and mean intensity of infestation were 13.3% and 3.3, respectively. At the same time, the list of sarcoptic mites occurring in Poland was completed with a new genus and new species--T. diversus.

The occurrence of Demodex spp. (Acari, Demodecidae) in the bank vole Myodes glareolus (Rodentia, Cricetidae) with data on its topographical preferences

An examination of 16 bank voles from Poland (Pomerania) revealed the presence of two species of the family Demodecidae (Acari, Prostigmata), specific to the host. Demodex buccalis Bukva, Vitovec et Vlcek, 1985 was noted only in one bank vole, where 18 specimens were found: the prevalence of infestation being 6.3%. D. glareoli Hirst, 1919 was observed in 75% of the examined bank voles, in which were on average 5.1 specimens. Additionally, mites of the both species exhibited topical specificity--representatives of D. buccalis were found in the tissues of the tongue and oral cavity of the host, while D. glareoli, being a species associated with hair follicles, was noted in skin specimens from different body areas, particularly the head area. Infestations with demodecids were not accompanied by disease symptoms. D. buccalis and D. glareoli are a new species for the fauna of Poland.

New for the fauna of Poland species of Psorergates spp. with the data of occurrence of mites from Psorergatidae family (Acari, Prostigmata) in native mammals

Five species of skin mites from Psorergatidae family have been found in four rodent species (Apodemus flavicollis, A. sylvaticus, Mus musculus, Myodes glareolus) coming from northern part of Poland. Three species (Psorergates microti, P. musculinus, P. simplex) appeared to be new ones for the fauna of Poland. Moreover A. sylvaticus and M. glareolus are a new hosts for P. apodemi, P. muricola, P. microti and P. musculinus from Poland. All developmental stages with immature stages predominance were found within particular species. The mites were found in skin fragments from different body areas, however they preferred head skin. The paper presents the list of species observed so far in Poland taking into consideration their hosts--currently the Psorergatidae fauna in Poland includes 10 species noted in eleven mammals species among rodents, bats and insectivores.

Demodectic mites of the brown rat Rattus norvegicus (Berkenhout, 1769) (Rodentia, Muridae) with a new finding of Demodex ratticola Bukva, 1995 (Acari, Demodecidae)

Demodex ratticola was recorded in the brown rat Rattus norvegicus from northern Poland. It is a skin mite specific to this host, previously recorded only in the Czech Republic. D. ratticola was found at a prevalence 65.0% and mean intensity 12.7 in skin samples taken from the regions of lips, nose and chin. Furthermore, three other species from the family of Demodecidae were recorded, including Demodex nanus found in skin samples from different parts of the body and characterised by the highest parameters of infestation (100.0%, 25.2), D. ratti (50.0%, 3.3) found in the head skin and D. norvegicus (30.0%, 3.5) found in the genital and anal regions. The identified demodectic mites did not cause any pathological symptoms in rats.

Demodex acutipes Bukva et Preisler, 1988 (Acari, Demodecidae)--a rare parasite of red deer (Cervus elaphus L.)

Two species of demodectic mites were described in the red deer Cervus elaphus, including Demodex kutzeri, which had also been found in other species of the Cervidae family in Austria, Germany, Czech Republic, Poland and North America. Whereas the other species, D. acutipes, had been previously known from only one finding in the Czech Republic. The present research included skin samples taken in winter 2012 from thirty red deer in northern Poland. Demodex acutipes (prevalence 20%, mean intensity 4.5), D. kutzeri (53.3%, 69.8) and fifteen Demodex sp. specimens (6.7%, 7.5), were found. D. acutipes is a new species for the fauna of Poland.

Occurrence of demodex spp. (Acari, Demodecidae) in the striped field mouse Apodemus agrarius (Rodentia, Muridae) in Poland

The hair follicle mites (Acari, Demodecidae) are obligatory and specific parasites of mammals, important in human and veterinary medicine. The family is represented by more than 100 species worldwide and 30 in Poland, therein 11 species (and 3 subspecies) were discovered from 10 species of native rodents. Fifty two striped field mice Apodemus agrarius from eastern Pomerania (Poland) were examined in 2006-2007; the presence of mites was confirmed by the standard method of digesting skin fragments (from head, belly, groin, limbs, genital-anal region, neck and back). Two demodectic mites were found: Demodex agrarii and D. arvicolae--specifically the form D. a. apodemi, previously recorded in the wood mouse (Apodemus silvaticus). Demodex spp. were noted in 53.8% of the examined mice; D. arvicolae was the dominant species (prevalence 48.1%, mean intensity 12.5), whereas D. agrarii was found in only a few hosts (prevalence 13.5%, mean intensity 7.6); these mites were more frequently found in males. D. a. apodemi were found mainly in skin of head and very few in skin of genital-anal region. D. agrarii lives in the ducts of the auricular sebaceous gland, in which all its developmental stages have been found; it is precisely the specific habitat of D. agrarii that determines its large size and its strongly elongated shape.

Demodex spp. (Acari: Demodecidae) in brown rat (Rodentia: Muridae) in Poland

The study on the demodecid fauna of the brown rat (Rattus norvegicus) revealed the presence of three species: Demodex nanus, D. norvegicus, and D. ratti, all three new for the fauna of Poland.

[Anoplura of rodents (Rodentia) in Northern Poland]

Anoplura of rodents (Rodentia) in Northern Poland. Above 100 rodents belonging to 6 species (Clethrionomys glareolus, Microtus agrestis, M. arvalis, Apodemus flavicollis, A. sylvaticus, Mus musculus) caught in the various habitations were examined. The parasites found represented three species of Anoplura: Hoplopleura acanthopus, H. affinis and Polyplax serrata. H. acanthopus appeard to be the most common parasite; it was found in all examined hosts, while mostly on the bank vole.

[Some aspects of the skin infestation by Demodex folliculorum]

The importance of demodicids (Demodex folliculorum and D. brevis) infestation and their effect on skin lesions has been described based on literature data and our own clinical and parasitological investigations. Hair follicle mites have been detected in 45% of patients with rosacea, 27% of patients with perioral dermatitis, 28% of patients suffering from seborrhoeic dermatitis and in 3 out of 7 patients with chronic blepharitis. Clinical picture of demodecosis included erythemato-papulous and pustulous (rosacea-like) skin lesions together with erythemato-desquamative changes of the face.

Demodex phylloides (Acari, Demodecidae) as a specific parasite of Sus scrofa (Mammalia, Artiodactyla)

Within 1994-2000, sections of skin collected from eleven areas on the body of 650 wild boars and 85 pigs living in the northern Poland and in the Great Poland were examined. The D. phylloides infestation in the wild boar was observed to be very heavy (prevalence 32%, mean intensity 74 ind.). In contrast, the domestic pig turned out to be free of the parasite. The wild boar D. phylloides infestations are symptomless. The parasite is relatively rare in the domestic pig, although the high animal density typical of farm stocks should aid in its spreading. Compared to that in the wild boar, the pigs affected show associated skin symptoms. Where demodicosis did occur, most often the entire population was suffering of the condition. Most probably, the wild boar is the original host of D. phylloides. The hair follicle mite in question is very frequent in the wild boar, but produces symptomless infestations. The parasite occurs more seldom in the domestic pig, but--in contrast--the infestations are much more violent.

The occurrence of parasitic arthropods in two groups of European bison in the Białowieza primeval forest

Within 1992-2000, a total of 181 Białowieza Forest bison were examined from two winter herds. Twelf parasitic arthropod species were observed, a high infestation being typical of Demodex bisonianius, Chorioptes bovis, Ixodes ricinus, Dermacentor reticulatus, and Bisonicola sedecimdecembrii. The infestation in section 422 herd being higher for B. sedecimdecembrii, I. ricinus, D. reticulatus, Ch. bovis. D. bisonianus was slightly more prevalent in the section 391 herd, the intensity being, however, lower than that in the other herd. Among the remaining arthropods found in the Bialowieza Forest European bison, some Lipoptena cervi occurred in both herds, Demodex sp. and Sarcoptes scabiei were recorded only in the section 422 herd, Ixodes persulcatus was present only in the section 391 bison and those kept in the reservation, while D. bovis, Psoroptes ovis, and Melophagus ovinus were found in the reserve bison only. In the present study, the largest differences in the extent of infestation involved the hair-dwelling arthropods (B. sedecimdecembrii, I. rixinus).

[Demodex ssp. (Acari, Demodecidae) in Mus musculus from Poland]

Two species (Demodex arvicolae and D. flagellurus) were collected in Mus musculus the first time in Poland. Also Myobia musculi was noted.