Parasite fauna of the water vole (Arvicola terrestris) and its nests in the south of Western Siberia

Fauna of parasitic and free-living arthropods associated the water vole Arvicola terestris and its nests in various landscape zones and subzones of the south of Western Siberia has been studied. Total abundance of gamasid mites and ticks (Gamasoidea, Ixodidae), fleas and nidicolous arthropods in nests is high, and the set of nidicolous and parasite species is quite diverse, but everywhere the parasite fauna is characterized by a small amount of species reaching a high abundance: Laelaps muris on the voles, Haemogamasus ambulans in nests, Ixodes apronophorus and Megpbotris walkeri both on the voles and nests. Parasitic arthropods living on the voles or in their nests are characterized by higher and stables indices of infection, while these parameters for free-living arthropods were variable. The list of mesostigmatic mites parasitizing the water vole and its nests in the south of Western Siberia (Adamovich, Krylov, 2001) has been considerably supplemented. In total, the fauna of parsitiform mites (Acari: Mesostigmata and Ixodiddes) and fleas (Siphonaptera) associated with the water vole in the south of Western Siberia is represented by 97 arthropod species of 19 families, including 74 species of mesostigmatic mites (Gamasoidea), 6 species of ticks (Ixodidae) and 17 species of fleas.     

Gamasid mites of common voles in the central Volga River region

The specific composition of gamasid mites from three species of voles (Microtus arvalis Pall., M. agrestis L., M. oeconomus Pall.) is given. Forest, field and flood-land groupings of the common vole having distinct phenotypical differences are characterized by differences in the structure of their parasite fauna. In the forest the number of meadow and meadow-field species decreases while that of forest species of mites regularly increases.     

Distribution of gamasid mites on small mammals in Yunnan Province, China

An investigation of gamasid mites on the body surface of small mammals was carried out in Yunnan Province of China from 1990 to 2004. The small mammal hosts were captured from 25 counties which represent five geographical subregions, namely Middle Subregion of Hengduan Mountains, Southern Subregion of Hengduan Mountains, Eastern Plateau Subregion of Yunnan, Western Plateau Subregion of Yunnan and Southern Moun- tainous Subregion of Yunnan. The captured 10 803 small mammal hosts belong to nine families, 29 genera and 52 species in four orders （Rodentia, Insectivora, Scandentia and Lagomorpha）. A total of 68 571 gamasid mites were collected from the body surface of the captured small mammal hosts and all the gamasid mites were identified to 10 families, 33 genera and 112 species. This paper lists all the mite species, together with their taxonomic position （genera and families） and their corresponding hosts. Much more mite species were found in the Middle Subregion of Hengduan Mountains than in other geographical subregions. The total individuals of mites and small mammals in the Middle Subregion of Hengduan Mountains are also the most plentiful in the five geographical subregions. Three dominant mite species and three dominant small mammal hosts were determined as the dominant species in the investigated areas of Yunnan Province. The dominant hosts are Rattus flavipectus （which accounts for 34.85% of the total individuals）, Apodemus chevrieri （13.43%） and Rattus norvegicus （10.40%） while the dominant gamasid mite species are Laelaps nuttalli （Hirst, 1915） （27.84%）, Laelaps echidninus （Berlese, 1887） （18.38%） and Laelaps guizhouensis （Gu et Wang, 1981） （14.79%）. The results showed the high species diversity of gamasid mites in Yunnan Province and the uneven distribution feature in different subregions.     

中国云南洱海周边小兽体表革螨多样性（英文）

云南大理洱海周边是我国流行性出血热的流行地区之一。本文目的是运用Shannon-Wiener、系统聚类分析方法（SPSS 13.0软件）和Levins'niche等对该区3 303只小兽体表寄生革螨的物种多样性、群落结构、相似性、分布和生态位进行研究。选择的洱海周边三个不同方位恰好处于东部无量山、南部哀老山和西部苍山,由于洱海的天然隔离使这三个方位形成了同地域异生境的地理景观。在调查点共捕获小兽宿主3 303只属4目（啮齿目、食虫目、攀鼩目和食肉目）7科15属21种,收集到的小兽体表寄生虫革螨23 196只被鉴定为6科16属43种。研究结果表明革螨群落结构复杂,物种多样性高。在不同方位革螨和它们相对应宿主的分布是不均匀的,但是洱海周边不同方位同样优势小兽上寄生的优势革螨种是一致的。结果暗示：生境影响着革螨和它们相对应小兽的物种构成和分布,如果小兽宿主的分类地位和生境相似,那么相对应的小兽宿主上的革螨群落就相似; 不同方位小兽体表寄生虫革螨的丰富度和物种多样性主要由宿主本身和宿主所栖息的生境决定;这可能是小兽和革螨之间协同进化在生态学上的一个佐证。但通过使用革螨的生态位宽度分析,革螨的宿主特异性很低,这又可能暗示着小兽和革螨之间有协同进化,但协同进化程度不高。     

Analysis of ectoparasites (chigger mites,gamasid mites,fleas and sucking lice) of the Yunnan red‐backed vole (Eothenomys miletus) sampled throughout its range in southwest China

The Yunnan red‐backed vole Eothenomys miletus (Rodentia: Cricetidae) is an endemic rodent species and reservoir host of zoonoses in southwest China. Based on a large host sample (2463 voles collected from 39 localities between 2001 and 2013), a general analysis of four categories of ectoparasite (fleas, sucking lice, chigger mites and gamasid mites) on E. miletus across its entire range of distribution was made. This analysis identified a total of 71 895 ectoparasites belonging to 320 species (30 species of flea, 9 of sucking louse, 106 of gamasid mite and 175 of chigger mite) with a high prevalence (87%), mean abundance (29.19) and mean intensity (33.69). Of the 18 vector species of zoonoses found on E. miletus, the flea Ctenophthalmus quadratus (Siphonaptera: Hystrichopsyllidae) and chigger mite Leptotrombidium scutellare (Trombidiformes: Trombiculidae) were the dominant species; these are the main vectors of zoonoses in China. All of the dominant parasite species showed an aggregated distribution pattern. Male voles harboured more species of parasite than females. Chigger mites represented the most abundant species group on voles and their prevalence was positively correlated with mean abundance (r = 0.73; P < 0.05). As a single rodent species, E. miletus has a high potential to harbour abundant ectoparasites with high species diversity and high rates of infestation. The sex of the vole affects ectoparasite infestation.     

云南省锡金小鼠体表革螨感染分析

为了解云南省锡金小鼠(Mus pahari)体表革螨的感染情况及分布规律,本研究基于1990至2015年云南省39个县(市)的调查数据,统计分析锡金小鼠体表革螨的基本感染情况和感染差异。使用聚块指数测定革螨空间分布型,用Jaccard指数计算革螨物种相似性。从捕获的720只锡金小鼠体表共采集到革螨14 098只,鉴定为2科12属37种。贵州厉螨(Laelaps guizhouensis)、贫毛厉螨(L. paucisetosa)和兴义厉螨(L. xingyiensis)是优势革螨,其在不同个体的锡金小鼠体表均呈聚集分布。不同地理景观中采集的锡金小鼠体表革螨的种类和数量相差大,山区景观中采集的锡金小鼠体表革螨的感染率Pm、平均多度MA和感染度MI均明显高于坝区景观中采集的个体(P0.05)。不同性别的锡金小鼠体表革螨物种中度相似,雄鼠的平均多度和感染度高于雌鼠(P 0.05)。种-样方关系图显示革螨物种数随宿主抽样量的增加而增加。结果表明,锡金小鼠体表革螨感染普遍,三个优势螨种在不同个体的宿主体表呈聚集分布,采自不同地理景观的锡金小鼠体表革螨构成差异较大。     

Characteristics of zonal distribution of the gamasid mites connected with small mammals and their nests in Western Siberia

Analysis of long-term data on the fauna, landscape distribution, and structure of communities of the gamasid mites (Acari:Parasitiformes:Mesostigmata) connected with small mammals and their nests in the plain part of Western Siberia is carried out. By now, presence of 249 gamasid mite species is established in the territory under study, including 193 free-living and 56 parasitic species. Gamasid mites are represented by the maximal number of species on small mammals and in thers nests in northern forest-steppe (102 and 105 species respectively). Nine parasitic species from two ecological groups (epizoic and nidicolous) were found in all landscape zones of the West Siberian Plain, namely: 1) epizoic species Laelaps clethrionomydis Lange, 1955, Laelaps hilaris C. L. Koch, 1836, and Hyperlaelaps arvalis Zachvatkin, 1948 (obligatory non-exclusive hematophagous); 2) nidicolous species Androlaelaps casalis Berlese, 1887 (obligatory non-exclusive hematophagous), Eulaelaps stabularis C. L. Koch, 1836, Haemogamasus nidiformnes Bregetova, 1955 (facultative hematophagous), Haemnogamnasus ambulans Thorell, 1872 (obligatory non-exclusive hematophagous), Hirstionyssus isabellinus Oudemans, 1913, and Hirstionyssus eusoricis Bregetova, 1956 (obligatory exclusive hematophagous). Last three species demonstrate the mixed type of parasitism. The population of gamasid mites on small mammals is most specific in tundra, southern forest-steppe and steppe; the fauna of gamasid mites in nests is most specific in southern forest-steppe and steppe.     

云南省小兽体表革螨名录初报

1994年至2004年在云南省境内共调查了25个县（市）,共捕获53种啮齿目、食虫目、攀口目、兔形目和翼手目小兽10803只,从其体表分检出革螨68572只,隶属10科26属80种,其中云南新记录种12种;结合相关文献记载,到目前为止,整个云南省小兽体表革螨共有10科33属112种。     

A review of gamasid mites (Parasitiformes,Mesostigmata) dwelling in the taiga of the Pechoro-Ilychskii Nature Reserve (northern Cis-Ural Region) with analysis of their assemblages in spruce forests

In the plain taiga of the Pechoro-Ilychskii Nature Reserve, 91 species of gamasid mites have been revealed. Cheiroseius (7 species), Veigaia (6), Arctoseius (5), Dendrolaelaps (5), and Dinychus (4) are the most diverse genera. European (29%), Palaearctic (27%), and Holarctic species (30%) are represented in the fauna by somewhat equal fractions, whereas cosmopolitan and semicosmopolitan species constitute about 14%. Comparison of gamasid assemblages populating certain habitats allowed revealing two distinct groupings, namely, forest and floodplain ones. Forest assemblages are characterized by high population density (220–760 ind./dm²) and by predominance of Parazercon radiatus, Zercon forsslundi, Veigaia nemorensis, Gamasellus montanus, and Trachytes spp. Floodplain assemblages are less abundant (80–130 ind./dm²) and comprise mainly meadow and hydrophilic species (A. cetratus, Cheiroseius spp. Gaeolaelaps spp., and Gamasellodes bicolor). Low diversity of the family Parasitidae (4 species) and structural peculiarities of assemblages dwelling in coniferous forests (namely, the absence of Pergamasinae and significant fractions of Veigaia, Gamesellus, Trachytes, and also of representatives of the family Zerconidae) demonstrate similarities between the mesostigmatan population of this northern European region and that of the Siberian taiga. Solitary records of such Arctic species as Arctoseius ornatus and Zerconopsis labradorensis, and of the hypoarcto-montane species Iphidinychus gaieri within the taiga belt, seem to reflect the instability of range margin. Taking into account the literary data, we recognize a complex of boreal and borealmountain species (Trachytes edleri, Dinychus septentrionalis. D. crassus, Caurozercon duplex, Neozercon smirnovi, Zercon forsslundi, and Z. zelawaiensis) in the Palaearctic fauna. Their habitats, however, are not restricted only to dark coniferous forest along. The structure of gamasid mite assemblages in mesophytic spruce forests of the Palaearctic varies strongly. By contrast to vascular plants, where many species accompany the dark coniferous taiga everywhere, there is not a single mesostigmatic mite species common to all the spruce forests analyzed, ranging from Romania in the west to Sakhalin Island in the east. On the whole, changes in gamasid mite assemblages across the spruce forest belt seem to follow a succession of meridional changes in gamasid faunas regardless of an edificatory spruce species.     

The effect of diet quality on gut anatomy in British voles (Microtinae)

Three species of British voles, the bank vole Clethrionomys glareolus, the field vole Microtus agrestis and the water vole Arvicola terrestris were maintained on diets of seed and plant leaf material to investigate changes in gut anatomy. C. glareolus and M. agrestis showed significant changes in most regions of the gut; they developed longer and heavier tracts when on a highfibre diet. This response may be important in enabling these animals to withstand seasonal changes in diet quality.     

The invertebrate fauna of High Arctic seabird nests: the microarthropod community inhabiting nests on Spitsbergen,Svalbard

The invertebrate fauna of the nests of three seabird species, black-legged kittiwakes (Rissa tridactyla), common eider (Somateria mollissima) and glaucous gull (Larus hyperboreus), were sampled in Kongsfjorden, Spitsbergen, Svalbard. The invertebrate community was species poor, consisting predominantly of the flea, Mioctenopsylla arctica arctica (Insecta: Siphonaptera), but with six species of oribatid mite (Acari: Oribatida), Diapterobates notatus, Oribatula tibialis, Ameronothrus lineatus, Hermannia reticulata, Trichoribates trimaculatus and Ceratoppia bipilis, plus an occasional mesostigmatid mite. No Collembola or ticks (Acari: Ixodidae) were observed. With the exception of M. arctica arctica, the fauna of seabird nests consisted of opportunistic microarthropod species rather than specialised nest-dwelling or bird parasitic species. Species diversity of soil oribatid mites was greater in nests of the common eider than compared to nests of the black-legged kittiwake, which may be related to the ground nesting behaviour of the common eiders. No rare or unusual microarthropod species for Svalbard were found in the seabird nests. The contentions that nests may facilitate microarthropod colonisation of High Arctic regions via bird phoresy by providing a high-quality habitat at the point of arrival, or that there might be a specialised microarthropod fauna exploiting this habitat, were not supported in this study. These are amongst the first data on the microarthropod community of seabird nests in the High Arctic.     

Experiments on habitat selection in voles: Implications for the inverse distribution of two common European species

Summary Several pairs of species of microtine rodents show inverse distributions or abundance. Here I determine if the inverse abundance relationship of the bank vole Clethrionomys glareolus (a forest species) and the field vole Microtus agrestis (an open field species) could be explained by habitat selection. Habitat selection was examined by choice experiments with combinations of soil and vegetation types, and with separate habitat factors. The effects of early experience and social behaviour were also studied, e.g. in a large outdoor enclosure. M. agrestis showed a stronger dependence on shelter (e.g. easily excavated soil or thick grassy vegetation) than C. glareolus, while the presence of preferred food did not affect habitat selection for either species. In both species, laboratory-bred specimens showed considerably fewer preferences. Habitat selection in subadult C. glareolus was influenced by social clumping, while territorial behaviour made more even distributions in M. agrestis.The less rigid habitat selection and weaker territorial behaviour observed in the forest species (Clethrionomys) compared with a species from temporary habitats (Microtus) is not consistent with present concepts of r- and K-selection.     

Arthropods in the nests of lesser spotted eagle (Aquila pomarina)

In 2001–2007, altogether 57 nests of lesser spotted eagle were collected in the Orava region in northwestern Slovakia and four groups of arthropods were extracted from them. Richest in number of species and individuals were mites (23 species, 17,500 ind.), followed by beetles (12 species, 725 ind.), whereas pseudoscorpions were represented only by Pselaphochernes scorpioides (39 ind.) and fleas by Ceratophyllus garei (3 ind.). Unlike nests of other birds, free-living mites predominated in the nests fauna (83% of individuals), followed by nidicolous species with more or less free relationship to the nests, while parasitic species represented only a negligible part of the fauna. For the first time we observed phoresy of Nenteria pandioni, a specific and abundant mite in the eagles’ nests, on the nidicolous staphylinid Haploglossa puncticollis. The beetle fauna in the nests was much poorer than in nests of other birds. The predatory H. puncticollis was dominant in the nests (83%) and occurred continuously during the whole investigation period. Other beetles, even the widely distributed nidicols such as the histerid Gnathoncus buyssoni, were found rarely in nests. Predators were also the only abundant trophic group of beetles in the nests, while other trophic groups of beetles abundantly co-occur in nests of majority of other birds. The occurrence of all beetles was very unevenly distributed during the investigation period, but was positively correlated with occurrence of mites. The relatively low number of species and individuals of mites and beetles in the lesser spotted eagle nests resulted from their position on tree tops, at a height of 20–30 m and their quick drying out by sun and wind. It was also indicated by an enormously low number of species and individuals of mycetophagous beetles, which represent a significant component of the fauna in nests of other birds.     

中国云南小兽寄生革螨的群落结构和空间分布

寄生在小兽体表的革螨可能是传播肾综合征出血热和立克次体痘等人兽共患病的媒介。本文报道了云南省28个县(市)小兽体表革螨的野外调查结果, 运用物种数、平均丰富度和Shannon多样性指数对小兽寄生革螨的群落特征和沿环境梯度的空间分布进行了研究, 并用系统聚类分析法 (SPSS 16.0软件)对18种主要小兽的革螨群落相似性进行了比较。在云南省28个县(市)共捕获到小兽14 544头, 隶属于5目（啮齿目、食虫目、攀鼩目、兔形目、食肉目）10科35属67种, 在捕获的小兽体表采集到革螨80 791头, 经鉴定属于10科33属112种。结果分析表明: 主要的宿主动物为黄胸鼠 Rattus tanezumi、齐氏姬鼠Apodemus chevrieri和大绒鼠Eothenomys miletus;纳氏厉螨Laelaps nuttalli、毒厉螨L. echidninus和贵州厉螨L. guizhouensis为革螨的优势种。齐氏姬鼠A. chevrieri、社鼠N. confucianus和黄胸鼠R. tanezumi体表寄生的革螨种类最多;臭鼩鼱Suncus murinus、齐氏姬鼠A. chevrieri和灰麝鼩Crocidura attenuata的革螨群落多样性最高。聚类分析结果表明, 大部分革螨群落的相似程度与相应小兽的亲缘关系及所处生态环境的相似性是基本一致的, 分类地位和生境选择相似的小兽, 它们的革螨群落也被聚为一类。革螨物种数沿纬度梯度的水平分布呈现两个峰值, 最大峰值出现在25°~26°N之间;沿海拔梯度的垂直分布呈单峰分布格局, 峰值在海拔2 000~2 500 m之间。革螨和小兽的多样性沿纬度梯度和海拔梯度的空间分布趋势也均表现出随着纬度和海拔的升高而先升高后降低的单峰型分布格局, 峰值分别出现在北纬25°~27°N和海拔2 000~2 500 m之间。结果提示云南革螨群落种类丰富, 多样性高。云南革螨物种数和多样性的分布格局可能直接受到古北和东洋两区系边缘效应的影响。     

Structure and Seasonal Dynamics of the Ectoparasite Community of the Pygmy Shrew <Emphasis Type="Italic">Sorex minutus</Emphasis> in the Ilmen-Volkhov Lowland

The species composition and seasonal dynamics of ectoparasites of the pygmy shrew Sorex minutus L., 1756 were studied in coniferous and mixed forests of the Ilmen-Volkhov Lowland (Novgorod Province of Russia) in 1999–2003. Examination of 265 specimens of the pygmy shrew revealed 670 specimens of ectoparasites that belonged to 13 species: 8 species of fleas, 2 species of ixodid ticks, 1 species of gamasid mites, and 2 species of myobiid mites. In total, 55.8% of shrew specimens were infested with ectoparasites. No more than 4 species of ectoparasites were found simultaneously on one host, and most of the examined shrews (64.8%) were infested with only 1 ectoparasite species. The pygmy shrew had lower infestation intensity and species diversity of acarines and fleas as compared with those of the common shrew Sorex araneus L., 1758 and the bank vole Myodes glareolus (Schreber, 1780) (13 vs. 23 and 29 species, respectively). Unlike these two other hosts, the prevalent ectoparasite of the pygmy shrew was the tick Ixodes trianguliceps Birula, 1895.     

Mite species inhabiting commercial bumblebee (<Emphasis Type="Italic">Bombus terrestris</Emphasis>) nests in Polish greenhouses

Nests of social insects are usually inhabited by various mite species that feed on pollen, other micro-arthropods or are parasitic. Well-known negative effects of worldwide economic importance are caused by mites parasitizing honeybee colonies. Lately, attention has focused on the endoparasitic mite Locustacarus buchneri that has been found in commercial bumblebees. However, little is known of other mites associated with commercial bumblebee nests. Transportation of commercial bumblebee colonies with unwanted residents may introduce foreign mite species to new localities. In this study, we assessed the prevalence and species composition of mites associated with commercial bumblebee nests and determined if the mites are foreign species for Poland and for Europe. The study was conducted on 37 commercial bumblebee nests from two companies (Dutch and Israeli), originating from two greenhouses in southern Poland, and on 20 commercial bumblebee colonies obtained directly from suppliers. The species composition and abundance of mites inhabiting commercial bumblebee nests were determined. Seven mite species from three families were found in nests after greenhouse exploitation. The predominant mite species was Tyrophagus putrescentiae (Acaridae) that was a 100-fold more numerous than representatives of the family Laelapidae (Hypoaspis marginepilosa, H. hyatti, H. bombicolens). Representatives of Parasitidae (Parasitellus fucorum, P. crinitus, P. ignotus) were least numerous. All identified mite species are common throughout Europe, foreign species were not found. Mites were not detected in nests obtained directly from suppliers. We conclude that probably bumblebee nests are invaded by local mite species during greenhouse exploitation.     

Giant sex chromosomes retained within the Portuguese lineage of the field vole (<Emphasis Type="Italic">Microtus agrestis</Emphasis>)

The field vole (Microtus agrestis) is characterised by extremely large blocks of heterochromatin on both the X and Y chromosome. Some other Microtus also have blocks of heterochromatin on their sex chromosomes but not as extensive and always of independent origin from the heterochromatic expansion found in M. agrestis. Coupled with evidence of geographic variation in large heterochromatic blocks within other species (e.g. in the western hedgehog Erinaceus europaeus), it might be expected that field voles would show substantial variation in size and disposition of the sex chromosome heterochromatin. In fact, only minor variation has been described up to now. Those studies conducted previously were largely on field voles from central and northern Europe. Here, we describe the karyotype of field voles from Portugal, of interest because recent molecular studies have shown field voles from western Iberia to be a separate evolutionary unit that might be considered a cryptic species, distinct from populations further to the east. The two Portuguese field voles (one female, one male) that we examined also had essentially the same karyotype as seen in other field voles, including the giant sex chromosomes, but with small differences in the structure of the Y chromosome from that described previously. The finding that field voles throughout Europe show relatively little variation in their giant sex chromosomes is consistent with molecular data which suggest a recent origin for this complex of species/near-species.     

SEX RATIO AND AGE STRUCTURE OF GAMASID MITES FROM SMALL MAMMALS IN WESTERN YUNNAN,CHINA*

Abstract A total of 70 species of gamasid mites (7485 individuals) were collected from the body surface of 38 species of small mammals (3023 individuals) during an investigation of 13 counties of western Yunnan, China, from 1990 to 1996. Most species of gamasid mites have more females (80% 100%) than males (P <0.01). Exceptions are Haemogamasus gongshanensis where males outnumber females (P < 0.01) and Haemolaelaps glasgowi where there are similar numbers of males and females (P > 0.05). No larva was found in most of the mite species. The proportion of individuals at the immature stages (mainly protonymphs and deutonymphs) in most mite species is small (0–12.84%) compared to the adults (P < 0.01). Exceptions are Ornithonyssus bacoti and Haemolaelaps glasgowi where 62.84% and 49.48% respectively are nymphs. The biased sex ratios may reflect the probable different bloodsucking preferences and parthenogenesis of the gamasid mites. The absence of larvae and a low proportion of nymph stages in most mite species probably reflect that the larvae or nymphs of most mite species are non‐feeding or non‐blood sucking and are in their hosts' nests. Another possibility is that some species directly produce protonymphs or even deutonymphs without eggs and larvae which makes it difficult to find the larval stage.     

Assemblages of dipterans (Diptera) in burrows of the European pine vole Microtus ( Terricola ) subterraneus Sel.-Long. in the “Les na Vorskle (Forest on the Vorskla River)” Nature Reserve (Belgorod Province)

Six species of bothrobiontic flies of 3 families (Phoridae, Helomyzidae, and Sphaeroceridae) were recorded from nests of the European pine vole Microtus (Terricola) subterraneus Sel.-Long. in Belgorod Province (“Forest on the Vorskla River” Nature Reserve). Four species are recorded in the fauna of Russia for the first time. Original Russian Text ? V.A. Krivokhatsky, E.P. Nartshuk, 2007, published in Entomologicheskoe Obozrenie, 2007, Vol. 86, No. 1, pp. 100–103.