中国云南小兽体表革螨多样性与生态分布

寄生在小兽体表的革螨是具有重要医学意义的节肢动物。本文用物种数、Simpson优势度指数、Shannon多样性指数、Pielou均匀度指数和主成分分析对云南省28县市5个动物地理小区小兽体表革螨的生态分布和多样性进行了比较分析。捕获的14544头小兽隶属于10科35属67种,共采集到革螨80791只,经分类鉴定属于10科33属112种。结果表明横断山中部小区革螨和小兽的物种丰富度和多样性指数均比其他动物地理小区的高。纳氏厉螨和毒厉螨是云南省的优势种和广布种,其生态分布和海拔没有明显的关系。与此相反,小兽宿主的分布因小区和海拔的不同而不同,黄胸鼠和褐家鼠主要分布于海拔1600m以下,而齐氏姬鼠、大绒鼠和中华姬鼠是海拔2600m以上的优势种。革螨和小兽的多样性表现出随海拔减少而降低的趋势。主成分分析结果表明宿主因素（物种丰富度和多样性指数）是影响革螨分布的主要因素,其次为降雨量和经度。云南省革螨的物种多样性与小兽的多样性密切相关。     

云南洱海周边地带社鼠体表寄生虫的群落组成（英文）

目的社鼠是东洋界种,不仅一直被认为是农林业有害动物,而且被怀疑为滇西北鼠疫疫源地的鼠疫、恙虫病和流行性出血热（汉坦病毒）等病原体的储存宿主。为了了解洱海周边地带社鼠体表寄生虫的多样性,我们研究了89只社鼠体表寄生虫的群落组成。方法选取云南洱海周边的不同地理方位作为野外抽样调查地点,用鼠笼加食饵诱捕小兽并检获其体表寄生虫。体表寄生虫在显微镜下鉴定寄生虫的种类。用染虫率和虫指数反映体表寄生虫的流行和密度状况,用统计分析中的非参数检验（Non-parametric Mann-Whitney U）分析雌雄小兽宿主间寄生虫数量差异,用Spearman相关分析（Spearman correlation analysis）体表寄生虫数量与宿主身体参数的关系。结果捕获89只社鼠,其中70只社鼠侵染体表寄生虫,总侵染率为79%。采集到体表寄生虫51种,包括31种恙螨、13种革螨、4种蚤及3种吸虱。攸氏无前恙螨为优势恙螨种,占恙螨总数的66.23%;土尔克厉螨为优势革螨种,占革螨总数的38.48%;绒鼠怪蚤为优势蚤种,占蚤总数的42.86%;太平洋甲胁虱为优势吸虱种,占吸虱总数的80.07%。这51种体表寄生虫中,有11种被证明是人类疾病的主要媒介。U检验表明,体表寄生虫、恙螨、吸虱、蚤类和革螨的个体数量和物种数在雌雄宿主体表间的差异无统计学意义。Spearman相关分析表明,体表寄生虫、恙螨、吸虱、蚤类和革螨的个体数量与宿主身体参数（体重）之间无相关性。结论社鼠的体表寄生虫群落结构复杂,物种多样性高,其中有11种曾经报道与人类疾病有关。社鼠主要的体表寄生虫为吸虱、蚤类、革螨和恙螨,社鼠很可能成为鼠疫、流行性出血热和灌丛斑疹伤寒等病原体的贮存宿主。     

Ectoparasitic insects and mites on Yunnan red-backed voles (Eothenomys miletus) from a localized area in southwest China

Ectoparasitic insects and mites on Yunnan red-backed voles (Eothenomys miletus) in Dali prefecture, Yunnan Province, southwest China, were studied between 2003 and 2004. In total, 34,389 individuals of 86 species of ectoparasitic insects (seven species of fleas and five species of sucking lice) and mites (23 species of gamasid mites and 51 species of chigger mites) were collected from 916 individual hosts. The diversity of ectoparasites on this single rodent species in such a small area was much higher than in previous reports, which concerned more host species and greater geographical areas. The majority of the ectoparasites were chigger mites, which accounted for 59.3 % of the parasite species and 87.4 % of the individual parasites. Most voles harbored parasites with an overall prevalence (P) of 82.5 % and mean abundance (MA) of 37.5 parasites per host. The dispersion coefficient (C) and patchiness index (m*/m) were used to study the spatial patterns of the seven dominant parasite species, and all seven had aggregated distributions. The species abundance distribution of the ectoparasites on the vole was fitted by Preston’s lognormal distribution (R ²?=?0.82), and the total expected parasite species was estimated from this plot as 167 species. Yunnan red-backed voles harbor many ectoparasites as revealed by examination of a large host population. Future field investigations should sample large numbers of host individuals to assess ectoparasite populations.     

From cuckoos to chickens: a caught-in-the-act case of host shift in feather mites (Arachnida: Acari: Psoroptoididae)

Feather mites are highly specialized permanent ectosymbionts recorded from all recently recognized bird orders. These mites, specialized to live in the plumage of their hosts, rarely cause any visible damage to their specific hosts. Recently described feather mite Allopsoroptoides galli Mironov (Acariformes: Psoroptoididae) was reported to cause severe mange in chickens in Brazil, leading to unprecedented economic losses. Until now, the natural host of A. galli remained unknown. In this paper, we report its true wild host, the Guira cuckoo Guira guira (Cuculiformes: Cuculidae). In addition, a previously unknown heteromorphic form of males is described from the mite population distributed on its natural host. We also speculate a possible scenario by which this mite species could have been horizontally transferred from the wild populations of the natural host to the secondary hosts.     

云南西部革螨生态位研究

本文应用现代生态学中生态位的理论和方法，对云南西部１１种主要革螨在２５种小兽宿主资源上的生态位宽度和生态位重叠进行了研究。生态位宽度用Ｌｅｖｉｎｓ模型测定；生态位重叠用Ｃｏｌｗｅｌｌ－Ｆｕｔｕｙｍａ模型测定，并在此基础上用模糊聚类分析进行了生态位重叠群的划分。研究结果表明：①１１种革螨中，纳氏厉螨及毒厉螨的生态位最宽，阿尔及利亚厉螨及金氏厉螨的生态位最窄；②模糊聚类分析将１１种革螨划分为７个生态位重叠群；③革螨生态位宽度与其所寄生的宿主范围呈正相关（ｒ＝０．８５０１，Ｐ＜０．０１），生态位宽度可作为评价革螨等体外寄生虫宿主特异性的定量指标。     

First observations in Turkish Thrace on water mite larvae parasitism of Ranatra linearis by Hydrachna gallica (Acari: Hydrachnidia)

Many aquatic insect species, including aquatic Hemiptera, are parasitized by water mite larvae. Although this situation may cause damaging impacts to the hosts, the mites can disperse and colonize new localities in this way. Little is known about the frequency of water mite ectoparasitism amongst the aquatic Hemiptera in Turkey. In this study, larval water mite parasitism on aquatic Hemiptera, which have been collected from different localities in Turkish Thrace, was evaluated. It was found that only nine individuals, belonging two different species in a total of 367 hemipteran specimens, were parasitized by larval water mites. Furthermore, variations in sizes and shapes of the mites on the waterscorpion Ranatra linearis Linne, 1758 and Nepa cinerea Linne, 1758 were determined. These are the first records for larval mite parasitism on R. linearis and N. cinerea in Turkish Thrace.     

Two new species of the feather mite family Gabuciniidae (Acariformes: Pterolichoidea) from wrens (Passeriformes: Troglodytidae)

Two new species of the feather mite family Gabucinidae (Acari: Astigmata) are described from birds of the family Troglodytidae (Passeriformes) from Central America: Piciformobia cinnycerthiae sp. nov. from Cinnycerthia unirufa (Lafresnaye) in Ecuador, and P. henicorhinae sp. nov. from Henicorhina leucosticte (Cabanis) in Costa Rica. These are the first records of mites of the genus Piciformobia Gaud et Atyeo, 1975 from passerine hosts. A renewed diagnosis of the genus Piciformobia and key to all known species are provided.     

Neoaulonastus grewlingi sp. nov. (Prostigmata: Cheyletoidea: Syringophilidae) a new quill mite species parasitizing Falcunculus frontatus (Passeriformes: Falcunculidae) in Australia

A new quill mite species Neoaulonastus grewlingi sp. nov. parasitizing Australian endemic Falcunculus frontatus (Latham) (Passeriformes: Falcunculidae) is described. This new species differs from N. caligatus Skoracki by the following characters: apunctate pygidial shield and coxal fields I–IV, setae c1 1.4 times longer than d1, and lengths of setae ve 20, si 15–25, se 155–175 and c2 145–155. This is the first record of syringophilid mites from hosts of the family Falcunculidae and first register of Neoaulonastus genus in Australian region.     

用分子生物学方法检测螨体内汉坦病毒的研究

目的 研究汉坦病毒(HV)在革螨、总螨体内增殖、定位等。方法 采用聚合酶链反应和原位分子杂交法检测革螨、总螨体内HV—RNA。结果 用PCR技术从革螨、总螨体内检测到HV—RNA，最低检测为5只螨组；取革螨和恙螨幼虫、若虫定期测定TCID50／m1滴度，证明HV在革螨、恙螨体内可经期传播并有增殖现象；用原位分子杂交技术在革螨、恙螨的卵巢细胞、支肠细胞等组织中检测到HV—RNA。结论 研究结果证明HV在螨体内可经期传播，并有增殖现象；HV通常定位于螨的卵巢和支肠细胞等组织内。为革螨、恙螨的媒介意义提供了具有分子水平的直接证据。     

Associations between innate immune function and ectoparasites in wild rodent hosts

Immune function is an important component of host fitness, and high investment in immunity should occur when the benefits outweigh the costs, such as when risk of parasitism is high. We sampled two rodent hosts, white-footed mice (Peromyscus leucopus), and prairie voles (Microtus ochrogaster), and their tick, flea, and mite ectoparasites. A bacterial killing assay was used to measure the host’s innate immune function. We hypothesized that classes of hosts (species, sexes, or age classes) with overall higher tick burdens would have a higher innate immune function as an evolutionary response to historically greater exposure. We hypothesized a weaker relationship between the fleas and mites and immune function because of high host specificity in fleas and the absence of known vector function in North American mites. Ectoparasites were significantly overdispersed on hosts. In accordance with our hypothesis, Peromyscus that had higher tick burdens also exhibited significantly higher bacterial killing ability compared to Microtus. There was no significant difference in total flea burden between rodent species and no relationship with bacterial killing ability. Microtus had higher burdens of mites in each order than Peromyscus, and female rodents had higher mite burdens than males. The benefits of maintaining high levels of innate immune factors appear to be greater than the energetic costs for Peromyscus compared to Microtus.     

Biological aspects of the house dust mite (dermataphagoides pteronyssinus) in relation to house dust atopy

To examine the validity of the old idea of the possible significance of mites for house dust atopy it was necessary to study the mite fauna of house dust. The most important findings in this investigation are that mites occur regularly, rather than occasionally, in house dust, and that the mite genus Dermatophagoides is represented by much higher numbers than any of the other genera found in dust.

Furthermore, it appears that there is a seasonal periodicity in the numbers of mites in dust with a maximum from August to October, and also that the numbers of mites in the dust from various houses differ considerably. House dust from high-mountain areas contains very few mites.

These observations fit very well with the knowledge of the seasonal and topographical variations in the allergen content of various dust samples.

Based on laboratory observations on the temperature and humidity requirements of Dermatophagoides, a model is constructed which makes the relation between the degree of dampness of houses and the numbers of mites in the dust understandable.

In this paper only very short mention is made of the many experiments showing the identity between the house dust allergen and the allergen produced by Dermatophagoides.

From the comparison of skin reactions to equivalent extracts of different species of mites it appears that the allergenic products of mites of one family tend to be identical.

     

Host specificity of Laelaps (Acari: Laelapidae) in central Brazil.

A study of associations between small mammals and ectoparasites in two adjacent nature reserves near Brasilia, Federal District, Brazil, revealed that ectoparasitic mites of the genus Laelaps Koch are host specific. Data on the prevalence and intensity of mite infestations were combined with measures of the reproductive activity of mite populations to estimate the association of each host-mite pair. Twelve morphologically distinct species of Laelaps occurred in monoxenous and oligoxenous associations with the cricetid rodent genera Oryzomys, Nectomys, Rhipidomys, and Calomys. Nine were referred to species recognized at the time of the study; three were described as new species in a recent publication. When mites initially assigned as the same species infested more than one host species, an examination of the morphological variation within and among mite specimens supported the hypothesis that mites infesting different hosts were reproductively isolated populations. Dispersal pathways apparently were restricted, occurring primarily between conspecific individuals. In one instance, two morphologically similar groups of Laelaps paulistanensis Fonseca were associated with two closely related rodent species, Oryzomys fornesi Massoia and O. nigripes (Olfers). Although the data presented here indicate that these two groups of mites are conspecific, further study is warranted.     

The bird ectoparasite Dermanyssus hirundinis (Acari, Mesostigmata) in the High Arctic; a new parasitic mite to Spitsbergen, Svalbard

Ectoparasites are common on birds and in their nests. Amongst these parasites are diverse gamasid mite species that can lead to irritation, disease transmission and blood loss. Few studies of the ectoparasites of birds breeding in the High Arctic exist. The parasitic mite, Dermanyssus hirundinis, was found in nests of snow buntings Plectrophenax nivalis nivalis, both natural nests and within nesting boxes, on Spitsbergen. Densities per nest varied from sporadic to greater than 26,000 individuals. This is the northernmost observation of this parasite. The mite was present in new nests, nests constructed the previous year and nests not utilized the previous summer. The parasite survives at least 18 months without access to a blood meal and can tolerate the Arctic winter, surviving temperatures below ?20°C. D. hirundinis is hence well adapted to arctic conditions. Only females were observed suggesting that this population is facultatively parthenogenetic.     

Metazoan ectoparasites of Atlantic mackerel, Scomber scombrus (Teleostei: Scombridae): macro- and microhabitat distribution

Parasites are affected by the environment where their hosts live, having a specific distribution among their hosts and occupying a well-defined microhabitat. The present work aims to describe the metazoan ectoparasite fauna of Scomber scombrus, namely its distribution at the macro- and microhabitat levels. For that, fish from two different Portuguese regions, Matosinhos (n?=?40) and Figueira da Foz (n?=?39), were examined for macroectoparasites. S. scombrus of Matosinhos presented four different parasite species, whilst fish from Figueira da Foz presented five species. All parasites belonged to Monogenea, Copepoda, or Isopoda. The main differences between infection levels of fish from the two localities were found in Grubea cochlear (higher infection levels in Matosinhos) and Caligus pelamydis (where the highest values were found in Figueira da Foz). Regarding the microhabitat of the reported ectoparasites, it could be seen that every species has a very specific distribution within the host: G. cochlear and Kuhnia scombri have a preference for the inner medial areas of gills, Kuhnia sprostonae for the pseudobranchs, and C. pelamydis for the internal wall of opercula. The numerical and functional responses to interspecific competition were absent. These results support the idea that the parasite driving forces of community structure are the reinforcement of reproductive barriers and the enhancement of chances to mate.     

Bat flies (Diptera: Streblidae, Nycteribiidae) and mites (Acari) associated with bats (Mammalia: Chiroptera) in a high-altitude region in southern Minas Gerais, Brazil

A total of 71 bat flies belonging to families Nycteribiidae and Streblidae, and 37 mites were collected on 12 species of bats (Phyllostomidae and Vespertilionidae) from the Chapada do Abanador (Minas Gerais, Brazil), between July 2009 and April 2010. Two new occurrences of ectoparasites were recorded on Histiotus velatus (bat fly Basilia producta) and on Carollia perspicillata (mite Parichoronyssus bakeri). Five new occurrences were recorded for the state of Minas Gerais, increasing the range for bat flies Anatrichobius passosi, Paraeuctenodes similis, Basilia juquiensis, Basilia producta and for mite Periglischrus vargasi. Moreover, two new species of mites were recorded for Brazil (P. bakeri and Macronyssus aff. leislerianus). With regard to infracommunities, the most frequent association was between Anastrebla modestini and Exastinion clovisi on bat Anoura geoffroyi. This study contributed to characterize the fauna of bat ectoparasites in representative but poorly-sampled environments of the Atlantic Forest, the campos de altitude (high altitude grasslands) and cloud forests of southern Minas Gerais.     

Spider mite allergy in apple-cultivating farmers: European red mite (Panonychus ulmi) and two-spotted spider mite (Tetranychus urticae) may be important allergens in the development of work-related asthma and rhinitis symptoms

BACKGROUND: Recent investigations have suggested that the citrus red mite (Panonychus citri) is the most important allergen affecting citrus-cultivating farmers with asthma, allergic rhinitis, or both. OBJECTIVE: We sought to evaluate type I hypersensitivity to spider mites, particularly the European red mite (Panonychus ulmi) and the two-spotted spider mite (Tetranychus urticae), and to determine the relationship between hypersensitivity to spider mites and respiratory dysfunction. METHODS: We performed a cross-sectional survey. Questionnaires were given, and skin prick tests for 11 inhalant allergens common in Korea and 2 species of spider mites (European red mite and two-spotted spider mite) were performed in 725 apple-cultivating farmers in Korea. RESULTS: Results of skin prick tests in the apple farmers indicated that European red mite (23.2%) was the most common sensitizing allergen, followed by Tyrophagus putrescentiae (21.2%), two-spotted spider mite (16.6%), Dermatophagoides farinae (16.3%), D pteronyssinus (14.4%), cockroach (13.1%), and Hop Japanese (Humulus Japonicus) pollen (12.0%). Positive skin responses (mean wheal size >/=3 mm) to one or more of 13 inhalant allergens were found in 48.2% of farmers tested, whereas 40 subjects (8.6%) had an isolated skin response to the spider mites. Among 119 farmers with work-related asthmatic symptoms, the positive skin response rates to European red mite and two-spotted spider mite were 40.4% and 27.0%, respectively. These figures were significantly higher than those found among farmers without work-related symptoms (19.1% and 14.1%, respectively; P <.01). The prevalence of work-related asthma symptoms was higher in farmers with positive skin responses to spider mites than in those with negative skin responses to spider mites and those with positive skin responses to any allergen tested (31.4% vs 15.0% vs 21.0%, respectively; P <.05). CONCLUSION: Spider mites, particularly European red mite and 2-spotted spider mite, are common sensitizing allergens in apple-cultivating farmers. These spider mites may be important causative allergens in the development of work-related respiratory symptoms in these workers.     

山东平原地区鼠体外寄生虫种类的调查研究

本文调查了山东平原地区鼠体外寄生虫分布及种类组成情况,为传染病防治、媒介生物控制提供科学依据.结果表明:在山东省内平原地区的5市(县)中共捕获鼠类286只;采获鼠体外寄生恙螨、革螨和蚤952只,共计7科12属17种,其中恙螨1科3属5种,革螨4科4属6种,蚤2科5属6种.     

Prevalence, mean intensity of infestation and host specificity of Spinturnicidae mites (Acari: Mesostigmata) on bats (Mammalia: Chiroptera) in the Pantanal, Brazil

Acari ectoparasites were collected from bats during 12 months in the Rio Negro farm (19°34′22″S and 56°14′36″W), Aquidauana, Mato Grosso do Sul. A total of 654 bats belonging to the families Phyllostomidae, Noctilionidae, Molossidae, Vespertilionidae and Emballonuridae were captured. Only 136 bats of nine genera and 11 species were parasitised. Periglischrus iheringi Oudemans was the most abundant mite species, and this prevalence may be related to the low degree of host specificity of this species and due to the broad geographical distribution of its hosts. The greatest mean intensity was found to Periglischrus torrealbai Machado-Allison on Phyllostomus discolor Wagner (Phyllostomidae) and Periglischrus tonatii Herrin and Tipton associated with Lophostoma silviculum d’Orbigny (Phyllostomidae), which also had the highest prevalence of infestation.     

The prevalence of house dust mites, Dermatophagoides spp, and associated environmental conditions in homes in Ohio

Abundance of the house dust mites, Dermatophagoides farinae and D. pteronyssinus, in various sites in the homes of dust-sensitive patients was sequentially monitored at approximately 3 wk intervals for 2 yr, and mite density was correlated with indoor physical and climatic factors. Significantly higher mite levels occurred on the most heavily used fabric-upholstered furniture and carpeted floor areas of the living/family room and bedrooms. Mattresses were not found to be the major foci for mites. No significant positive correlation was noted between mite abundance and frequency or thoroughness of cleaning, amount of dust, and age of furnishings or dwelling. Significantly higher mite levels occurred on carpeted floors than on noncarpeted floors. Successive vacuuming did not significantly reduce mite abundance. Mite density exhibited a seasonal fluctuation, with highest density occurring in the humid summer months and the lowest density during the dryer, late heating season. Live mites were more abundant than dead mites during the period when total abundance was high. In homes inhabited by both species, D. farinae was the dominant species, except in one home that had a significantly higher relative humidity.     

Skin-scale genetic structure of <Emphasis Type="Italic">Sarcoptes scabiei</Emphasis> populations from individual hosts: empirical evidence from Iberian ibex-derived mites

The objective of the present study was to examine the extent of genetic diversity among Sarcoptes scabiei individuals belonging to different skin subunits of the body from individual mangy hosts. Ten microsatellite primers were applied on 44 individual S. scabiei mites from three mangy Iberian ibexes from Sierra Nevada Mountain in Spain. Dendrograms of the mites from the individual Iberian ibexes, showing the proportion of shared alleles between pairs of individual mites representing three skin subpopulations (head, back, and abdomen subunits), allowed the clustering of some mite samples up to their skin subunits. This genetic diversity of S. scabiei at skin-scale did not have the same pattern in all considered hosts: for the first Iberian ibex (Cp1), only mites from the head subunit were grouped together; in the second individual (Cp2), the clustering was detected only for mites from the abdomen subunit; and for the third one (Cp3), only mites from the back subunit were clustered together. Our results suggest that the local colonization dynamics of S. scabiei would have influenced the nonrandom distribution of this ectoparasite, after a single infestation. Another presumable explanation to this skin-scale genetic structure could be the repeated infestations. To our knowledge, this is the first documentation of genetic structuring among S. scabiei at individual host skin-scale. Further studies are warranted to highlight determining factors of such trend, but the pattern underlined in the present study should be taken into account in diagnosis and monitoring protocols for studying the population genetic structure and life cycle of this neglected but important ectoparasite.