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在检视大量革螨标本中,发现异形标本4种9例。异形包括骨板变形和刚毛变位两种情况,现分别记述如下,供革螨分类鉴定和形态学研究时参考。1 毒厉螨 Laelaps echidninus Berlese,1887 检视标本1608■■,发现异形4■■。1971年2-10月采于吉林省前郭尔罗斯蒙古族自治县,寄主为褐家鼠 Rattus noruegicus(Berkenhout)。 标本1:胸板后缘明显凹陷,后凸的骨片消失(图1-2),该处构造与正常标本不同。肛板花纹如图1,后部有一圆锥形构造,向后突出,PA位于其后…  相似文献   

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Meiosis is described in a thelytokous strain of the anoetid mite Histiostoma feroniarum (Dufour) and in both sexes of the arrhenotokous strain of this species. Oogenesis in the thelytokous strain is accomplished by ameiotic mitosis with only one pseudo-maturation division. During this division one or more chromosomes may move to the poles precociously and while in this position can be mistaken for centrioles. Fourteen chromosomes are found at metaphase of the pseudo-maturation division and in cleaving eggs of this strain. In the arrhenotokous strain, male meiosis consists of a single mitotic division. Oogenesis is regular and 7 bivalents are observed at the first maturation division. Metaphases of the first cleavage division in fertilized eggs show 14 chromosomes and 7 chromosomes in unfertilized eggs.It is postulated that the thelytokous strain has arisen from the arrhenotokous strain. This assumption is in agreement with that suggested for several insect species previously reported. The evolution in the Acari and the variability in the modes of reproduction in this suborder are discussed in light of the findings in this paper on the Anoetidae.  相似文献   

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A faunal list of oribatid mites collected from the summit of the Cheviot, Northumberland, is given, together with notes on the taxonomy and distribution of several of the species. Special attention is paid to the Arctic-alpine and European-alpine species and the list provides further support for the view that the upland areas of Britain are characterized by a common group of oribatid species. It is suggested that these species may be cold hardy or cold tolerant with relatively high supercooling points, enabling them to survive the winter at these higher altitudes.  相似文献   

6.
Functional responses of deutonymphs of the predatory mite,Allothrombium pulvinum Ewing, on eggs and adult females of two-spotted spider mite,Tetranychus urticae Koch, were determined in the laboratory. Predation experiments were conducted on lima bean leaf discs over a 24-h period at 25±2°C, 30–50% RH and 24L: 0D photoperiod. Prey densities ranged from 10 to 120T. urticae eggs per disc or 2 to 32 adult females per disc.Allothrombium pulvinum deutonymphs were more effective againstT. urticae eggs than its adult females. The role ofA. pulvinum deutonymphs in integrated and biological pest control is discussed.  相似文献   

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Most mites of the family Trombidiidae are ectoparasites in the larval stage and free-living predators in the deutonymphal and adult stages on a variety of arthropods, among which are pests of many economic crops. This paper provides an updated review of their systematics, life history, reproduction, behaviour, predator-prey and parasite-host relationships, and population dynamics, with particular reference to their possible role in biological control. © Rapid Science Ltd. 1998  相似文献   

8.
Laboratory crossing experiments indicate that populations of A. limonicus sensu lato collected from cassava (Manihot esculenta Crantz) in Brazil (Cruz das Almas) and Colombia (Palmira and Monteria) are conspecific and different from A. limonicus Garman & McGregor sensu stricto collected in Riverside, California, USA and Jaguariuna, Brazil. A. limonicus s.l. did not cross with A. tenuiscutus, A. rapax or A. limonicus s.s.. A. limonicus s.s. did not cross with A. rapax. Populations of A. aerialis, A. anonymus and A. idaeus from Colombia are conspecific with Brazilian populations of these species.  相似文献   

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Several species of phytoseiid mites (Acari: Phytoseiidae), including species of the genera Amblyseius, Galendromus, Metaseiulus, Neoseiulus, Phytoseiulus and Typhlodromus, are currently reared for biological control of various crop pests and/or as model organisms for the study of predator-prey interactions. Pathogen-free phytoseiid mites are important to obtain high efficacy in biological pest control and to get reliable data in mite research, as pathogens may affect the performance of their host or alter their reproduction and behaviour. Potential and verified pathogens have been reported for phytoseiid mites during the past 25 years. The present review provides an overview, including potential pathogens with unknown host effects (17 reports), endosymbiotic Wolbachia (seven reports), other bacteria (including Cardinium and Spiroplasma) (four reports), cases of unidentified diseases (three reports) and cases of verified pathogens (six reports). From the latter group four reports refer to Microsporidia, one to a fungus and one to a bacterium. Only five entities have been studied in detail, including Wolbachia infecting seven predatory mite species, other endosymbiotic bacteria infecting Metaseiulus (Galendromus, Typhlodromus) occidentalis (Nesbitt), the bacterium Acaricomes phytoseiuli infecting Phytoseiulus persimilis Athias-Henriot, the microsporidium Microsporidium phytoseiuli infecting P. persimilis and the microsporidium Oligosproridium occidentalis infecting M. occidentalis. In four cases (Wolbachia, A. phytoseiuli, M. phytoseiuli and O. occidentalis) an infection may be connected with fitness costs of the host. Moreover, infection is not always readily visible as no obvious gross symptoms are present. Monitoring of these entities on a routine and continuous basis should therefore get more attention, especially in commercial mass-production. Special attention should be paid to field-collected mites before introduction into the laboratory or mass rearing, and to mites that are exchanged among rearing facilities. However, at present general pathogen monitoring is not yet practical as effects of many entities are unknown. More research effort is needed concerning verified and potential pathogens of commercially reared arthropods and those used as model organisms in research.  相似文献   

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The aim of the paper was to determine the infestation parameters and species composition of eriophyoid mites for different parts of Norway spruce and Scots pine as well as for different age groups of the trees. The observations on the occurrence of the mites were conducted in 2004 and 2005 in 4 locations distributed in various regions of Poland, accounting for 11 environments (location x year). Three plant age groups were studied: (1) adult trees: 40–60 years old, additionally divided into three levels: top, middle and bottom; (2) young trees: 6–10 years old; and (3) seedlings: 2–3 years old. The same number of species (five) occurred on each coniferous tree, but only one, the rarest, was common on both tree species. Out of 500 samples for each species, mites were found on 279 pine (55.8%) and 252 spruce samples (50.2%). No tendency for the mites to choose any particular level on Scots pine and Norway spruce was observed. In addition, no tendency for the mites to choose trees from any of the age groups was observed for both Scots pine and Norway spruce, in the latter case the result obtained also for mite species subdivided into vagrant and refuge-seeking ones. Final conclusions were that in case of adult trees samples can be taken from the bottom part of a tree; however, sampling from young trees growing among adult trees may be seen as the most efficient sampling method.  相似文献   

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In this paper I synthesize original and published studies of sperm transfer behaviour of 23 genera of water mites from 15 families. The morphology of spermatophores from 16 genera (12 families) is described. Behaviour and/or spermatophores are described for the first time for the following species: Hydrachna magniscutata Marshall, Hydrachna hesperia Lundblad, Hydrachna sp. nr. leegei Koenike, Limnochares americana Lundblad, Limnesia undulata (Müller), Neumania distincta Marshall, Unionicola (three species in the U. crassipes-complex), Thyas slolli Koenike, Lebertia annae Habeeb, Lebertia sp., Piona sp. nr. debilis (Wolcott), Tiphys vernalis (Habeeb), Arrenurus dentipetiolatus Marshall, Arrenurus marshalli Piersig and Arrenurus birgei Marshall. On the basis of proximity of male and female during sperm transfer, I divide water mites into four groups: complete dissociation, involving no physical or chemical contact between the sexes (nine genera); incomplete dissociation, requiring distance-or contact-chemoreception but not involving pairing behaviour (five genera); pairing with indirect transfer, involving pairing behaviour with females controlling sperm uptake (three genera); pairing with direct transfer (=copulation), involving pairing behaviour and male placement of sperm in the receiving structure of the female (12 genera). Four genera have representative species in more than one category of sperm transfer. Factors possibly leading to the diversity of water mite mating behaviour include an evolutionarily flexible mode of sperm transfer in the ancestral water mite, and the development of planktonic and endoparasitic habits in many mites. Morphological features of spermatophores that improve physical stability, probability of females taking up sperm and resistance against osmotic stress are discussed. Finally, I present implications of mating behaviour and spermatophore morphology for phylogenetic relationships within water mites and between this group and terrestrial Acari.  相似文献   

12.
Mustafa Akyol  Kamil Koç 《Biologia》2006,61(2):125-132
Three new species of Neophyllobius viz. N. demirsoyi, N. yunusi, N. bolvadinensis and male, protonymph and larvae of N. lachishensis Bolland, 1998 from Turkey are described and illustrated. Neophyllobius lachishensis is reported from Turkey for the first time.  相似文献   

13.
Acari (mites and ticks) form one the most diverse lineages of arthropods, but basal relationships in the group are still poorly understood. The current study addresses this issue for one of its two main lineages, the order Parasitiformes. Relationships are examined at the subordinal and infraordinal level using complete 18S and partial 28S nuclear rRNA sequence data. Most currently recognized lineages are recovered with good support, suggesting that nuclear rRNA, and specifically 18S rRNA, is very well suited for analyzing relationships at this level in this lineage. These results were found despite quite variable rates of sequence evolution, with rates "ratcheting up" from relatively low in most non-mite arachnid lineages, to intermediate in Pseudoscorpiones, the mite order Acariformes, and the parasitiform suborders Opilioacarida, Holothyrida, and Ixodida, to high in the parasitiform suborder Mesostigmata. The most species rich mesostigmatid infraorder, Dermanyssina, shows huge distances to the outgroups, but remarkably low within-group divergence in nuclear rRNA. This suggests the possibility of a relatively recent origin of this lineage.  相似文献   

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Halacarid mites (Acari), with almost 700 species described, inhabit marine and freshwater habitats. The majority of genera are recorded from at least two ocean basins or continents. There is no evidence of endemic genera, in either littoral faunal provinces or in deep-sea regions. Copidognathus, a genus comprising 1/4 of all species described, is found in almost all geographic regions, depths and habitats. Other genera dominate or are restricted to cold waters, to warm waters or to distinct habitats.Corresponding habitats on either side of the boreal Atlantic Ocean harbour congeneric, identical, sibling or morphologically similar species. The fauna in the western Atlantic is less diverse than that in the eastern. Amphiatlantics are restricted to certain genera. Transatlantic distribution is independent of the niche inhabited.Of the marine halacarid species recorded from the boreal western Atlantic, 41% are amphiatlantics, while only one species is recorded from both the Caribbean and the Mediterranean. The Caribbean and the Mediterranean faunas are dominated by genera in which amphiatlantics are unknown.Most of the Black Sea species of the genus Halacarellus also occur in the Baltic, North Sea or North Atlantic, whereas the Copidognathus fauna of the Black Sea is similar to that of the Mediterranean.Halacarids are thought to be an ancient taxon, with most genera probably having been present since the Mesozoic and with several species having an age of at least 50 million years. Evidence for their antiquity is found in the distributional pattern of marine and limnic genera and species, in the lack of endemic genera despite low fecundity and lack of dispersal stages, and in the fact that amphiatlantics are restricted to certain genera without relationships to the niches inhabited.  相似文献   

16.
The larvae of Hydrachnellae can be divided into three types, based on the habits of the parasitic (larval) stage in the life cycle. (1) The larvae do not leave the water. Parasitizing aquatic insects, they are permanently submerged and wet. Only some species of the family Hydrachnidae belong to this type. (2) The larvae leave the water. The parasitic phase occurs either on insects living on the water surface, or in the air stores of aquatic insects. In both cases the larvae are not in direct contact with water during the parasitic phase. The Limnocharidae, Eylaidae and some species of the Hydrachnidae belong to this type. (3) The larvae parasitize insects which live in the air and which can leave the direct proximity to water; therefore it may be difficult for the mite larva to return to water. Except for the Hydrachnidae, Limnocharidae and Eylaidae, all families of the Hydrachnellae belong to this type.  相似文献   

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1. Reproductive strategies of four species of oribatid mites were investigated in the Chihuahuan Desert from 1981 to 1984.
2. Breeding activity coincided with the summer rainfall period in three of the four cases: Passalozetes neomexicanus, P. californicus and Jornadia larreae. This pattern was not changed by the application of simulated rainfall at other times of the year. The strict seasonality of reproductive behaviour is interpreted as an outcome of strong selection pressure to recruit only when food quality and quantity and microclimate are most favourable.
3. Joshuella striata showed a more flexible pattern which was essentially bimodal. Periods of egg production occurred in winter and also during the summer rainfall period. This pattern is consistent with the known distribution of this species in winter- and summer-rainfall deserts in south-western USA.  相似文献   

18.
Many phytophagous mites can attack strawberry plants, Fragaria x ananassa, among them the southern red mite, Oligonychus ilicis McGregor, and the two-spotted spider mite, Tetranychus urticae Koch. They are found together feeding on the same plant on the upper and underside of the leaves, respectively. Here we studied the choice for feeding sites of O. ilicis and T. urticae on strawberry plants. The first hypothesis tested whether the feeding site choice would be related to the fitness of the species. The second hypothesis dealt whether the feeding site would be determined by the presence of a heterospecific mite. We evaluated the preference, biology and reproductive success of O. ilicis and T. urticae on the under and upper side surface of strawberry leaves infested or not by the heterospecific. O. ilicis preferred to stay on the upper side surface while T. urticae preferred the underside. The preference for the leaf surface correlated with the reproductive success of the species (measured by the intrinsic growth rate). The choice pattern of feeding sites did not alter when the choice test was applied using sites previously infested by heterospecific. Although O. ilicis and T. urticae, apparently, do not interact directly for feeding sites, there is a chance that the first species induces defenses in strawberry plant enabling to reduce the fitness of the second species. The possibility of those species stay together on strawberry plant increases the damage capacity to the culture.  相似文献   

19.
Ilse Bartsch 《Hydrobiologia》2008,595(1):317-322
Halacarid mites have successfully invaded the sea and approximately 56 species colonized the freshwater. Invasion from the sea into continental waters probably started in the Mesozoic or Pre-Mesozoic and went on in the following epochs. The number of genera (14) and species (34) recorded from the Palaearctic is remarkably higher than that of other geographical regions. These numbers do not imply that the Palaearctic is a centre of origin, they reflect the sampling activity rather than reliable data on diversity. Guest editors: E. V. Balian, C. Lévêque, H. Segers & K. Martens Freshwater Animal Diversity Assessment  相似文献   

20.
Unstable microhabitats (merocenoses)—such as decayed wood, ant hills, bird and mammal nests—constitute an important component of forest (and non-forest) environments. These microhabitats are often inhabited by specific communities of invertebrates and their presence increases the total biodiversity. The primary objective of the present study was to compare communities of Uropodina (Acari: Mesostigmata) inhabiting soil and unstable microhabitats in order to explore the specificity of these communities and their importance in such ecosystems. Uropodine communities inhabiting merocenoses are often predominated by one or two species, which constitute more than 50 % of the entire community. Many species occur commonly in particular merocenoses, but are absent or rare in soil and litter, for example, Allodinychus flagelliger, Metagynella carpatica, Oplitis alophora, and Phaulodiaspis borealis. The biology of Uropodina inhabiting unstable microhabitats is modified by the adaptations required for living in such habitats. Mites associated with merocenoses developed special dispersal mechanisms, such as phoresy, which enable them to migrate from disappearing environments. Communities of Uropodina in soil and litter predominately consisted of species which reproduce parthenogenetically (thelytoky), whereas in merocenoses bisexual species prevail.  相似文献   

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