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1.
It has been stated that small organisms do not have barriers for distribution and will not show biogeographic discreteness. General models for size-mediated biogeographies establish a transition region between ubiquitous dispersal and restricted biogeography at about 1–10 mm. We tested patterns of distribution versus size with water mites, a group of freshwater organisms with sizes between 300 μm and 10 mm.We compiled a list of all known water mite species for Sierra del Guadarrama (a mountain range in the centre of the Iberian Peninsula) from different authors and our own studies in the area. Recorded habitats include lotic, lentic and interstitial environments. Species body size and world distribution were drawn from our work and published specialized taxonomic literature. The null hypothesis was that distribution is size-independent. The relationship between distribution and size was approached via analysis of variance and between size and habitat via logistic regression. Contrary to expectations, there is no special relationship between water mite size and area size distribution. On the other hand, water mite size is differentially distributed among habitats, although this ecological sorting is very weak. Larger water mites are more common in lentic habitats and smaller water mites in lotic habitats. Size-dependent distribution in which small organisms tend to be cosmopolitan breaks down when the particular biology comes into play. Water mites do not fit a previously proposed size-dependent biogeographical distribution, and are in accordance with similar data published on Tardigrada, Rotifera, Gastrotricha and the like.  相似文献   

2.
青海省寄生螨类的区系分布   总被引:2,自引:0,他引:2  
张文生  李明立 《昆虫知识》1996,33(2):105-107
根据建国以来的大量研究调查资料,对青海地区已记载的寄生螨类(主要包括革螨、恙螨)计10科33属100余种进行了初步的区系分布、数量与宿主关系的探讨。(1)河湟谷地小区[1]:计有45种,主要有:赛氏血革螨、秉氏血革螨、旱獭青厉螨、毒厉螨、鼠兔赫刺螨、褪色巨螯螨、似田鼠新恙螨、旱獭新恙螨等;(2)柴达木盆地小区:计有15种,具代表性种类为乌兰纤恙螨;(3)祁连青南小区:计有85种,具代表性种类为久治真棒恙螨、玉树羽叶恙螨和朱雀禽棒恙螨;(4)羌塘高原小区:计有3种,皆为血厉螨属种类。  相似文献   

3.
The water mites of running waters in The Netherlands have been surveyed for the period 1987–1992. The aims were to investigate their present distribution, to make a comparison with historical data and to identify differences in water mite assemblages on a regional scale. The investigation covered 821 sites in eight different drainage areas. In spite of the scarcity of historical data, it may be concluded that in the course of this century about 40% of rheophilic water mites have become extinct. In canalized streams lentic species are dominant. In springs and spring streams, lotic species can survive, but the assemblages consist mainly of euryoecious water mite species.Multivariate techniques were used to show regional differences. These differences are mainly determined by stream hydraulics. The area of Zuid-Limburg can easily be demarcated by its relatively high number of rheophilic species. The man-made streams (sprengen) at the east side of the Veluwe area are characterized by a number of species which indicate undisturbed circumstances. The response of water mites to pollution of running waters is discussed.  相似文献   

4.
In the alpine region at Finse, Norway, Phauloppia spp. (Acari, Oribatida) inhabit lichens on top of boulders. Adult mites are about 0.5 mm in length and have a mean weight of ca. 15 μg. Temperatures in the lichens may drop below -35 degrees C in winter and increase to 55 degrees C in the summer. Large seasonal variations were recorded in supercooling points and body fluid osmolality. Mean January values of SCPs and osmolality were -35.3 degrees C and 3756 mOsm, while July values were -9.4 degrees C and 940 mOsm, respectively. Thermal hysteresis proteins were present in both summer and winter acclimated mites. In mid-winter, some of the mites survived more than 49 days in a water vapor saturated atmosphere at -19 degrees C, and more than 42 days enclosed in ice at the same temperature.The mites showed high tolerance to desiccation. Specimens collected in October survived up to 23 days at 22 degrees C and 5% RH. The tolerance to desiccation was lower in specimens collected during the winter. Some mites survived the loss of up to 90% of their total water content and were reactivated when given access to water. Length measurements of individual Phauloppia sp. showed that both male and female mites are clearly divided in two size groups, suggesting that they belong to two closely related species or different populations.  相似文献   

5.
Although mites are one of the most abundant and diverse groups of arthropods, they are rarely targeted for detailed biodiversity surveys due to taxonomic constraints. We address this gap through DNA barcoding, evaluating acarine diversity at Churchill, Manitoba, a site on the tundra-taiga transition. Barcode analysis of 6279 specimens revealed nearly 900 presumptive species of mites with high species turnover between substrates and between forested and non-forested sites. Accumulation curves have not reached an asymptote for any of the three mite orders investigated, and estimates suggest that more than 1200 species of Acari occur at this locality. The coupling of DNA barcode results with taxonomic assignments revealed that Trombidiformes compose 49% of the fauna, a larger fraction than expected based on prior studies. This investigation demonstrates the efficacy of DNA barcoding in facilitating biodiversity assessments of hyperdiverse taxa.  相似文献   

6.
A large number of coastal dune waters in the Netherlands and northwestern France have been investigated for the occurrence of water mites. Dune waters turned out to be very rich in water mite species. In the Dutch dunes, 110 species of water mites have been found; this is 50 % of the total number of water mite species present in the Netherlands. In the French dunes 64 species have been found. The water mites most characteristic of the coastal dunes are the temporary water species. Dune areas with a high-lying hinterland have a water mite composition much different from dune areas with a low-lying hinterland. This can be explained by the existence of a very different hydrology. During the last century human activity affected the ground water of dunes. Afforestation and extraction of ground water for drinking water purposes caused a lowering of the ground water table. As a result, many dune slacks dried out. Moreover, the infiltration of river water caused an eutrophication of the ground water. Nowadays, the dunes most rich in typical water mite species are the dunes in which neither infiltration of river water nor extraction for drinking water purposes, occur. It can be concluded that water mites are good indicators for dune areas with a natural hydrology.  相似文献   

7.
The ectoparasite fauna on the most widespread synanthropic chiropteran species, the particolored bat (Vespertilio murinus L., 1758), is described from localities in the Urals and West Siberia. 86 individual bats have been examined, off which 463 ectoparasite specimens from 8 species have been collected. The species composition and ecology of these arthropods are analyzed. The core of the ectoparasite fauna on the particolored bat in the Urals has been found to consist of gamasine mites of the genus Steatonyssus.  相似文献   

8.
The paper reports the results of eight-year investigations on the ectoparasites of rodents and insectivores carried out in southern taiga of the Ilmen-Volkhov lowland (Novgorod Region) and Kurgolovsky reserve (Leningrad Region). Twelve species of small mammals were captured including three dominate species--bank vole Clethrionomys glareolus (2722 specimens), common shrew Sorex araneus (1658 specimens), and wood mouse Apodemus uralensis (367 specimens). Parasite community of the bank vole comprises 34 species of mites, ticks, and insects, the community of common shrew comprises 25 species, and the community of A. uralensis includes 28 species. Taxonomic diversity of the ectoparasite communities was shown to be based on the diversity of types of parasitism and ecological nishes of the host body. Permanent ectoparasites are found to be represented by 2 species of lie and 14 species of acariform mites. The group of temporary parasites includes 13 species of fleas, 10 species of gamasid mites. 3 ixodid species and 1 Trombiculidae. There is a common pool of temporary parasites of small mammals in the ecological system of taiga. Significance of different shrew and rodent species as hosts were found to be dependent on the population density in possible hosts and many other factors. Species diversity in the parasite communities of different small mammal species is dependent on the number of possible ecological nishes in the host body. Actual infill of these nishes by ectoparasites is usually lesser than potential one. Species composition of temporary parasites, their occurrence and abundance changes according to season. Interspecific competition in the temporary parasite species can decrease because of the seasonal disjunction of their population peaks. Diversification of the ecological niches of ectoparasites allow simultaneous feeding of more parasite individuals on one host, than in the case of parasitising of single species or several species with similar ecological nishes. The distribution of parasites on their hosts was also studied. The aggregative distribution has been found in ixodid larvae only, and the distribution of fleas was close to the Poisson distribution. Deviations from the aggregative distribution can be an effect of several independent factors, including limited ability of small mammals for providing numerous parasites with food. On the most part of hosts simultaneous parasitizing of no more than 1-3 individuals of each tick, mite, and flea species was registered. Excessive infestation by ectoparasites may probably be limited by effective reactions of self-purification in the mammal hosts.  相似文献   

9.
记述采自江西的蚌螨属1新种,定名为丰城蚌螨Unionicola(Parasitatax)fengchengensis sp.nov.和1个中国新纪录种。  相似文献   

10.
An intensive survey of ectoparasitic arthropods associated with small mammals in upland forests near Manaus, Brazil, provides information on the taxonomy and host distribution of laelapine mites in the Amazonian Region. We identified 5 genera and 21 species of these mites by comparison with representative museum specimens, the taxonomic literature, and, when possible, the original type specimens. These mites are host specific, with associations ranging from strict monoxeny (18 species) to oligoxeny (1 species) and pleioxeny (2 species). Marsupials were infested with species of Androlaelaps, echimyid rodents with Tur, and sigmodontine rodents with Gigantolaelaps, Laelaps, and Mysolaelaps. Androlaelaps bergalloi, a new species of Laelapinae, is described from the pelage of the marsupial Monodelphis brevicaudata.  相似文献   

11.
The application of molecular markers to the study of ticks and mites has recently yielded new insights into their population structures and taxonomic relationships. Ticks have been studied at individual, population and species level. Mites are a more diverse group and those that have been studied to the same degree as the ticks include the Tetranychidae (spider mites), Phytoseiidae (predatory mites) and the Eriophyidae. Population variation has also been studied in the important bee parasitic mite Varroa jacobsoni Oudemans. The methods used to study these organisms have much in common. At the individual level these range from general approaches, such as AFLP, RAPD or DALP, to highly specific microsatellite analysis. Although these markers also work at the population and species level, additional analysis of specific nuclear or mitochondrial genes has been conducted either by RFLP or sequencing. Molecular applications have had particular success in facilitating the identification of taxonomically difficult species, understanding population structures and elucidating phylogenetic relationships.  相似文献   

12.
The specific composition of acarid mites occurring in dust of rural dwellings in the Far East of the USSR has been first studied and characters of their fauna have been revealed. 3 species are most frequently encountered of which Dermatophagoides pteronyssinus accounts for 56% of all finds. 6 species happened to be new for the fauna of dwellings. The typical synanthropic species Glycyphagus domesticus is totally absent from dwellings but occurs in 90% of honey-bee hives.  相似文献   

13.
The host specificity and population genetic structure of the symbiotic water mites Unionicola foili from the host mussel Utterbackia imbecillis and Unionicola formosa from the mussels Pyganodon cataracta, Pyganodon grandis and Anodonta suborbiculata were examined over a broad geographical scale in order to determine the extent to which specialization by these water mites is structured geographically. The behavioural responses of U. foili and U. formosa were highly host-species specific, with adults of both species exhibiting negative phototaxis in the presence of a chemical factor from the species of mussel with which the mites had been associated in the field. The photobehaviour of these water mites in the presence of water from a non-host mussel varied depending on the species in question. Although U. foili from U. imbecillis exhibited negative phototaxis in water modified by A. suborbiculata, mites from this latter host did not exhibit a directional response in U. imbecillis water. Unionicola foili and U. formosa from A. suborbiculata were positively phototactic when they were exposed to water modified by either species of Pyganodon. The photoresponse of U. formosa from P. cataracta and P. grandis was positive in the presence of water modified by U. imbecillis and A. suborbiculta. However, these mussel-mites showed no directional response in water modified by their alternate species of Pyganodon. Unionicola foili and the host-associated populations of U. formosa were examined for allozyme variation at eight loci to determine the pattern and degree of genetic variation. There was a high degree of genetic differentiation when mite populations from the two species of Pyganodon were compared with U. foili or U. formosa from A. suborbiculata. These populational groupings were fixed for different alleles at two enzyme loci. The results of this study indicate that populations of U. formosa from P. cataracta and P. grandis are reproductively isolated from U. foili from U. imbecillis and from U. formosa from A. suborbiculata and contend that host specificity is an important mechanism in restricting gene flow among these populational groupings. Furthermore, this study indicates that specialization among unionicolid water mites can vary geographically, owing to differences in geographic distribution of available hosts and differences in host use.Exp Appl Acarol 22: 683697 © 1998 Kluwer Academic Publishers  相似文献   

14.
Water mites (Acari: Hydrachnida) are unusual among the typically cryptic freshwater fauna in that many species are brightly colored red or orange, and also appear to be distasteful to fish. This apparent aposematism (use of color to warn predators) has been previously explained as the evolutionary end-product of pressure from fish predation. The fish-predation argument has been supported by observations that fish spit out red mites, powder made from red water mites is more distasteful to fish than powder made from non-red mites, and red mites appear to be more abundant than non-red mites in water bodies where fish are present. In this paper, we challenge the hypothesis that fish were the sole driving force behind the evolution of aposematism in water mites. We show that non-red mites actually dominate in water bodies with fish, and that red mites are more abundant in temporary, fishless water bodies. We also demonstrate that powder made from red, terrestrial velvet mites (Trombidiidae) was as distasteful to fish as powder made from red water mites. We suggest that the main role of red and orange carotenoid pigments may be to act as photoprotectants, and hypothesize that redness originated in the terrestrial ancestors of water mites and has been retained in certain lineages of water mites after the invasion of the aquatic habitat. We also suggest that distastefulness evolved subsequent to bright coloration in response to increased conspicuousness to predators. Relaxed selection for redness has occurred when adults and/or larvae are less exposed to sunlight, either through occupying more protected habitats, parasitizing more nocturnal hosts, or parasitizing hosts for a short period of time. Our ability to test this alternative hypothesis is hampered by lack of knowledge of the source and mode of action of distastefulness, and of phylogenetic relationships among the Parasitengona.  相似文献   

15.
用U检验和相关分析的统计方法对2003~2004年云南洱海(中国滇西北著名的淡水湖泊)周边251只大足鼠体表寄生螨进行了调查.调查点是我国11大鼠疫自然疫源地之一,也是我国恙虫病和出血热的流行地区.大足鼠已经被鉴定为鼠疫、汉坦病毒、恙虫病和流行性出血热的储存宿主.我们的研究发现大足鼠携带好几种与人兽共患病有关的螨类.为了丰富大足鼠体表寄生螨的研究,在此,对大足鼠的体表寄生螨群落和体表寄生螨医学和兽医学的重要性进行了描述.有191只大足鼠寄生有体表寄生螨,侵染率为76%.采集到的体表寄生螨有35种,包括15种恙螨和20种革螨.其中6种以前已经被证明是人类疾病的主要媒介.因此大足鼠很显然成为流行性出血热和恙虫病等病原体的贮存宿主.  相似文献   

16.
Water mites (Acari: Hydrachnida) are unusual among the typically cryptic freshwater fauna in that many species are brightly colored red or orange, and also appear to be distasteful to fish. This apparent aposematism (use of color to warn predators) has been previously explained as the evolutionary end-product of pressure from fish predation. The fish-predation argument has been supported by observations that fish spit out red mites, powder made from red water mites is more distasteful to fish than powder made from non-red mites, and red mites appear to be more abundant than non-red mites in water bodies where fish are present. In this paper, we challenge the hypothesis that fish were the sole driving force behind the evolution of aposematism in water mites. We show that non-red mites actually dominate in water bodies with fish, and that red mites are more abundant in temporary, fishless water bodies. We also demonstrate that powder made from red, terrestrial velvet mites (Trombidiidae) was as distasteful to fish as powder made from red water mites. We suggest that the main role of red and orange carotenoid pigments may be to act as photoprotectants, and hypothesize that redness originated in the terrestrial ancestors of water mites and has been retained in certain lineages of water mites after the invasion of the aquatic habitat. We also suggest that distastefulness evolved subsequent to bright coloration in response to increased conspicuousness to predators. Relaxed selection for redness has occurred when adults and/or larvae are less exposed to sunlight, either through occupying more protected habitats, parasitizing more nocturnal hosts, or parasitizing hosts for a short period of time. Our ability to test this alternative hypothesis is hampered by lack of knowledge of the source and mode of action of distastefulness, and of phylogenetic relationships among the Parasitengona.  相似文献   

17.
黄丽琴  郭宪国  吴滇  王乔花 《昆虫学报》2009,52(12):1328-1337
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。  相似文献   

18.
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.  相似文献   

19.
Feather mites (Astigmata) are specialized parasites living on the plumage and skin of birds. The paper presents data on infestation of some passerines (Passeriformes) by feather mites in the south of Western Siberia (Omsk and Tyumen Provinces). We found 24 species of feather mites belonging to the families Analgidae, Dermoglyphidae, Pteronyssidae, Trouessartiidae, and Proctophyllodidae on 16 bird species. Among them, 19 species are common parasites of the passerine birds examined; five species were detected on atypical hosts. Ten mite species were recorded for the first time on the passerine species examined. Analysis of the distribution of abundant and common mite species on their hosts has demonstrated that the majority of the bird parasites possess a specific distribution pattern in the host plumage with preference for certain feather types. We have also obtained new data on host associations of several mite species.  相似文献   

20.
The karyotypes of water mites (Acari: Hydrachnellae: Hydrodromidae) are largely unknown. The present investigation is the first report of a study designed to characterize the chromosomes of water mites. The study was carried out with specimens of Hydrodroma despiciens collected from Eber Lake in Afyon, Turkey. Several different methods were tried to obtain chromosomes of this species. However, somatic cell culture proved to be the most effective for the preparation of chromosomes. In the present study, we determined the diploid chromosome number of Hydrodroma despiciens to be 2n = 16. However, a large metacentric chromosome was found in each metaphase, which we believed to be the X chromosome. We could not determine the sex chromosomes of this species. This study is the first approach to the cytogenetic characterization of this water mite group. Furthermore, these cytogenetic data will contribute to the understanding of the phylogenetic relationship among water mites. To our knowledge, this is the first report on the cytogenetics of water mites.  相似文献   

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