Dispersal patterns of oribatid mites across habitats and seasons

Oribatid mites are tiny arthropods that are common in all soils of the world; however, they also occur in microhabitats above the soil such as lichens, mosses, on the bark of trees and in suspended soils. For understanding oribatid mite community structure, it is important to know whether they are dispersal limited. The aim of this study was to investigate the importance of oribatid mite dispersal using Malaise traps to exclude sole passive wind-dispersal. Oribatid mite communities were collected over a 3-year period from five habitat types (coniferous forests, deciduous forests, mixed forests, meadows, bog/heathlands sites) and three seasons (spring, summer, autumn) in Sweden. Mites entered traps either by walking or by phoresy, i.e., by being attached to flying insects. We hypothesized (1) that oribatid mite communities in the traps differ between habitats, indicating habitat-limited dispersal, and (2) that oribatid mite communities differ among seasons suggesting that dispersal varies due to changing environmental conditions such as moisture or resource availability. The majority of the collected species were not typically soil-living species but rather from habitats such as trees, lichens and mosses (e.g., Carabodes labyrinthicus, Cymbaeremaeus cymba, Diapterobates humeralis and Phauloppia lucorum) indicating that walking into the traps or entering them via phoresy are of greater importance for aboveground than for soil-living species. Overall, oribatid mite communities collected in the traps likely originated from the surrounding local habitat suggesting that long distance dispersal of oribatid mites is scarce. Significant differences among seasons indicate higher dispersal during warm and dry periods of the year. Notably, 16 species of oribatid mites collected in our study were sampled for the first time in Sweden. This study also demonstrates that Malaise traps are a meaningful tool to investigate spatial and temporal patterns of oribatid mite communities.

     

Bacterial communities in predatory mites are associated with species and diet types

The symbiotic bacterial communities of phytophagous arthropods are affected by host species and feeding habits, but such effects have been poorly studied in natural enemies. Here, we investigated the entire bacterial microbiome of two species of predatory mites, Neoseiulus californicus and Neoseiulus barkeri, feeding on three types of diets (artificial diet, pollen and their natural prey, the spider mite Tetranychus urticae) by high-throughput sequencing of the 16S rRNA gene. We found that the bacterial diversity of predatory mites feeding on artificial diet was significantly different from pollen and spider mite feeding groups in both N. californicus and N. barkeri, while bacterial diversity also differed strikingly between the two species even when feeding on the same artificial diet. This finding suggests that the bacterial community of predatory mites is determined by both species and diet. Alphaproteobacteria and Gammaproteobacteria were the two dominant bacterial classes in both predatory mite species, except for N. californicus feeding on artificial diet. The bacterium Bosea sp. was detected in all samples as the core microbial species in predatory mites. Additionally, we discuss whether Bradyrhizobiaceae and Rhodobacteraceae bacteria could be used as probiotics in the artificial diet of N. californicus for better mass rearing.

     

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.     

Generalist-feeding subterranean mites as potential biological control agents of immature corn rootworms

Predatory mites are important components of subterranean food webs and may help regulate densities of agricultural pests, including western corn rootworms (Chrysomelidae: Diabrotica virgifera virgifera). Implementing conservation and/or classical biocontrol tactics could enhance densities of specialist or generalist predatory mites and lead to pest suppression, but first relevant mite species must be identified and their predatory capabilities evaluated. We conducted lab assays to quantify consumption of immature rootworms and oviposition rates of various mite species. Our study indicates that rootworms are a sub-optimal food source for the mite taxa tested. However, all mite species fed upon rootworms to some degree, although consumption by nematophagous Eviphis ostrinus was extremely low. Predators consumed more rootworm larvae than eggs, and mite size was correlated with prey consumption, with larger predators eating more prey. Four mite taxa (Gaeolaelaps sp., S. miles, Gl. americana, and G. aculeifer) had detrimental effects on survival of rootworm larvae, and the latter two species also had negative impacts on densities of pest eggs. Although it is unlikely that any of these mite species by itself has a major impact on rootworm control, the community of generalist soil-dwelling mites may play an important role in regulating immature rootworm populations in the field.     

The coconut mite, Aceria guerreronis, in Benin and Tanzania: occurrence, damage and associated acarine fauna

The coconut mite Aceria guerreronis (Eriophyidae) is considered the most important pest of coconut fruits in Africa; however, quantitative knowledge about its distribution and abundance is lacking. We conducted four diagnostic surveys—three in Southern Benin and one along the coast of Tanzania—to determine the distribution of A. guerreronis and the severity of its damage to coconut fruits, as well as the diversity and abundance of other associated mites and potential natural enemies. Aceria guerreronis was found in all visited plantations with the percentage of damaged fruits varying considerably among plantations—67–85% in Benin and 43–81% in Tanzania. Overall, 30–40% of the fruit surfaces were damaged by A. guerreronis. Damage severity increased with fruit age and negatively affected fruit weight of 7- to 12-months-old fruits. Aceria guerreronis was by far the most abundant mite on coconut fruits but its abundance depended on fruit age. The highest densities of A. guerreronis were observed on 3- to 4-months-old fruits. Neocypholaelaps sp. (Ameroseiidae) was the most abundant mite on inflorescences. Three species of predatory mites (Phytoseiidae)—Neoseiulus baraki, N. neobaraki and N. paspalivorus—were the most commonly found predatory mites beneath the coconut bracts in association with A. guerreronis. Neoseiulus neobaraki was the prevailing predator in Tanzania while N. paspalivorus was the most frequent predator in Benin. Other mites found beneath the bracts were the herbivore Steneotarsonemus furcatus (Tarsonemidae) and the detritivore and fungivore Tyrophagus putrescentiae (Acaridae).     

Phoretic mites and nematode associates of Scolytus multistriatus and Scolytus pygmaeus (Coleoptera: Scolytidae) in Austria

Abstract 1 The species assemblages and abundance of phoretic mites and nematodes associated with the elm bark beetles, Scolytus multistriatus and Scolytus pygmaeus, were studied in Austria. 2 A total of 3922 individual mites were recorded from 144 adults of S. multistriatus and 178 adults of S. pygmaeus. The species spectrum was identical and the relative abundance of mites was very similar for both species of scolytids. Nine mite species, Pyemotes scolyti, Pseudotarsonemoides eccoptogasteri, Trichouropoda bipilis, Tarsonemus crassus, Proctolaelaps eccoptogasteris, Proctolaelaps scolyti, Chelacheles michalskii, nr. Eueremaeus sp. and Elattoma sp. were detected. Two of the nine species, nr. Eueremaeus sp. and Elattoma sp., are documented here as new associates of Scolytus spp. 3 Pyemotes scolyti was the most frequent mite species, and Ps. eccoptogasteri and T. bipilis were relatively common, whereas the other mites occurred occasionally or were rare. 4 The trophic roles of most of the mites associated with S. multistriatus and S. pygmaeus are poorly known, but they may include fungivores, parasitoids of bark beetle broods, predators of bark beetle broods and/or mites and/or nematodes. 5 Besides phoretic mites, two nematode associates were seen on the investigated insects. A species of Cryptaphelenchus occurred under the elytra of both scolytid species, whereas the adults of a Neoparasitylenchus sp. were present inside abdomens of S. multistriatus, but absent from S. pygmaeus.     

Abundances and host relationships of chigger mites in Yunnan Province,China

This paper reports on ectoparasitic chigger mites found on small mammals in Yunnan Province, southwest China. Data were accumulated from 19 investigation sites (counties) between 2001 and 2009. A total of 10 222 small mammal hosts were captured and identified; these represented 62 species, 34 genera and 11 families in five orders. From the body surfaces of these 10 222 hosts, a total of 92 990 chigger mites were collected and identified microscopically. These represented 224 species, 22 genera and three subfamilies in the family Trombiculidae (Trombidiformes). Small mammals were commonly found to be infested by chigger mites and most host species harboured several species of mite. The species diversity of chigger mites in Yunnan was much higher than diversities reported previously in other provinces of China and in other countries. A single species of rodent, Eothenomys miletus (Rodentia: Cricetidae), carried 111 species of chigger mite, thus demonstrating the highest species diversity and heaviest mite infestation of all recorded hosts. This diversity is exceptional compared with that of other ectoparasites. Of the total 224 mite species, 21 species accounted for 82.2% of all mites counted. Two species acting as major vectors for scrub typhus (tsutsugamushi disease), Leptotrombidium scutellare and Leptotrombidium deliense, were identified as the dominant mite species in this sample. In addition to these two major vectors, 12 potential or suspected vector species were found. Most species of chigger mite had a wide range of hosts and low host specificity. For example, L. scutellare parasitized 30 species of host. The low host specificity of chigger mites may increase their probability of encountering humans, as well as their transmission of scrub typhus among different hosts. Hierarchical clustering analysis showed that similarities between different chigger mite communities on the 18 main species of small mammal host did not accord with the taxonomic affinity of the hosts. This suggests that the distribution of chigger mites may be strongly influenced by the environment in which hosts live.     

Species status and population genetic structure of grapevine eriophyoid mites

Bud mite, blister mite (Colomerus vitis Pagenstecher), and rust mite (Calepitrimerus vitis Nalepa) (Acari: Eriophyoidae) are recognized grapevine pests. Much of the biology and ecology of these pests is poorly understood. We used two types of molecular markers to gain further insight into the breeding biology and population structure of these mites, using individuals collected from sites around south‐eastern Australia. Patterns of genetic variation observed using PCR‐RFLP of ITS 1 (Internal Transcribed Spacer 1) confirmed the separate species status of the rust mite, and resolved the species status of bud and blister mites, revealing two closely related but distinct species. Microsatellite markers revealed extensive genetic differentiation between bud mite populations and blister mite populations even at micro‐geographical levels, suggesting low movement in these species. The findings indicate that separate control strategies are needed against bud and blister mites, and that localized control strategies are likely to be effective given their limited dispersal.     

Parasite-host associations and life cycles of spring-living water mites (Hydrachnidia, Acari) from Luxembourg

Larval water mites are parasites of various insect species. The main aim of the present study was to analyse the host range of spring dwelling water mites. The investigation focuses on seven spring sites in Luxembourg. Some 24 water mite species were recorded either from the benthos or as parasites attached to flying insects captured in emergence traps. For 20 mite species 35 host species from four Nematocera (Diptera) families were recorded. About 80% of the host species and over 90% of the host individuals were Chironomidae, the others were Limoniidae, Dixidae and Simuliidae. For all water mite species recorded we present the observed host spectrum and/or potential hosts as well as the intensity of parasitism and the phenology of the mites. For 10 mite species the hosts were previously unknown. For another ten species the known host spectrum can be confirmed and extended. The host spectrum ranged from one host species (e.g. for Sperchon insignis) to at least 10 host species (for Sperchon thienemanni, Ljania bipapillata), but the effective host range could not be definitively estimated due to the lack of corresponding data. The hypothesised host preference of the water mites, of which most are strictly confined to spring habitats, for similarly spring-preferring hosts could not be proven. The mean intensity of parasitism was highest for Thyas palustris (10.8 larvae/host) and lowest for Sperchon insignis and Hygrobates norvegicus (1.2 larvae per host for each). The hydryphantid mite Thyas palustris occurred at maximal intensity (41 larvae per host) and the two abdominal parasites Ljania bipapillata and Arrenurus fontinalis showed higher mean intensities than the thoracic parasites did. Larval water mites parasitising chironomids did not exhibit a preference for host sex. The phenology of the larval mite species was varied, some species were only present in samples early in the year and others exclusively in the summer. Another species showed two peaks of occurrence, springtime/early summer and late summer/autumn. In conclusion, the water mite larvae in the studied springs showed differences in host spectra and phenology but there are no clear evidences in both for host partitioning. Maybe, the relative low species diversity of water mites in individual springs and the low inter-specific competition for suitable hosts in combination with the high host abundances and species richness makes springs such favourable habitats for the mites.     

Aerial dispersal of European red mites (Acari: Tetranychidae) in commercial apple orchards

Aerial dispersal of European red mite, Panonychus ulmi (Koch), in commercial apple orchards was estimated by trapping windborne mites. Studies were conducted at four orchards in eastern New York during 1989 and 1990 and at three orchards in western New York during 1989. In each orchard mites were trapped in three locations; the interior of the orchard, at the border of the orchard and in a field or woodlot beyond the orchard. Large numbers of mites were captured, even when the numbers of mites on apple foliage were well below levels where mite injury to leaves was visible (less than five per leaf). The log numbers of mites trapped were linearly related to the log density of mites on leaves and this relationship was consistent for each year and region the study was conducted. The trap captures among the three locations in and outside an orchard were highly correlated. The implications these findings may have on metapopulation dynamics and resistance to acaricide dynamics are discussed.     

Effect of different wave lengths of light on the behaviour of an Eriophyid bud mite, Aceria sheldoni

The effect of daylight passing through Cellophane filters on the behaviour of the eriophyid mite, Aceria sheldoni Acarina: Eriophyidae, was examined.The sensitivity of this mite to different wave lengths of light was demonstrated. The most attractive colours of Cellophane filters, beneath which the mites settled for feeding and reproduction, were the red and yellow, in contrast to the blue and green ones.

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Zusammenfassung Die Wirkung von Tageslicht nach Durchgang durch Cellophan-Filter auf das Verhalten der Eriophide Aceria sheldoni (Ewing), Acarina: Eriophidae, wurde untersucht, Dabei ließ sich die Empfindlichkeit dieser Milbe gegenüber Licht verschiedener Wellenlängen nachweisen. Die anziehendsten Cellophan-Filter-Farben, unter denen die Milben zu Nahrungsaufnahme und Fortpflanzung schritten, waren Rot und Gelb, im Gegensatz zu blauen und grünen Filtern.

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Contribution from the Volcani Institute of Agricultural Research, Bet Dagan, Israel. 1969 Series, No. 1455-E.

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This work is a section of a research project which was financed in part by a grant from the U.S. Department of Agriculture under P.L. 480.     

Can the red palm mite threaten the Amazon vegetation?

The red palm mite Raoiella indica Hirst (Tenuipalpidae) was first reported in the New World in 2004, dispersing quickly and widely while adopting new plant species as hosts. Since then, it has caused severe damage in this region, especially to coconut (Cocos nucifera L.). It was first found in Brazil in 2009, in the northern Amazonian state of Roraima. In the present study, native and introduced plants were sampled between March 2010 and February 2011 in sites of the 15 Roraima municipalities, to estimate its distribution and the associated mite fauna. In addition, monthly samples were taken from a coconut plantation in Mucajaí throughout the same period, for an initial appraisal of the levels R. indica could reach. It was found in 10 municipalities, on 19 plant species of four families. Six species are reported for the first time as hosts. Among the associated predators, 89.1% were Phytoseiidae, most commonly Amblyseius largoensis (Muma), Iphiseiodes zuluagai Denmark & Muma and Euseius concordis (Chant). The highest densities of R. indica, 1.5 and 0.35 mites/cm² of leaflet (approx total of 331 and 77 mites/leaflet), were reached respectively in March 2010 and February 2011. The highest density of phytoseiids on coconut (0.009 mites/cm² or about 2 mites/leaflet) was reached in November 2010. The average densities of R. indica recorded for Roraima were comparable to those reported for countries in which the mite is reportedly economically damaging. The dispersal of R. indica through the Amazon forest may result in damage to cultivated and native palms, and plants of other families, if the projected increase in both the frequency and the severity of drought events occurs. Parts of the Amazon have undergone periods of low rainfall, a condition that appears to favour the biology of this mite. Its eventual arrival to northeastern Brazil may result in heavy economic and ecological losses.     

Three‐year surveillance (2016–2018) of chigger mites vector for tsutsugamushi disease in the Hwaseong‐Si area of Gyeonggi‐Do,Republic of Korea

Owing to climate change, the global resurgence of vector‐borne infectious diseases has emerged as a critical public health issue. Orientia tsutsugamushi is the etiological agent of tsutsugamushi disease (scrub typhus) a mite‐borne acute febrile disease occurring in the Asia‐Pacific region. We investigated the prevalence of tsutsugamushi disease transmitted by chigger mite vectors living on rodents. Using sticky‐type chigger traps for three months during 2016–2018, 1,057 chigger mites were collected (chigger mite index, 1.31) from four locations in the Hwaseong‐si area of Gyeonggi‐do, Republic of Korea. Five species distributed among three genera were identified. In addition, 94 rodents were captured (collection rate: 7.83%) using Sherman live traps over the course of three months (April, October, and November) during 2016–2017. Three rodent species were captured and identified and the striped field mouse (Apodemus agrarius) was the dominant rodent host species in the surveyed area. A total of 10,469 ectoparasitic chigger mites were recovered from the 94 rodents, from which 13 species distributed among four genera were identified. Of the 5,250 chigger mites examined, Leptotrombidium pallidum was most abundant (n = 2,558), followed by L. orientale, L. scutellare, L. zetum, Euschoengastia koreaensis, L. subintermedium, and Neotrombicula tamiyai. Of the examined chigger mites, no groups recovered from rodent hosts tested positive for O. tsutsugamushi. This study provides fundamental regional information on vector‐borne disease data collection in the Hwaseong‐si area, Gyeonggi‐do, and will further contribute to formulating disease control and prevention strategies.     

Immigration of Phytoseiid Mites from Surrounding Uncultivated Areas into a Newly Planted Vineyard

This study reports (1) a faunistic survey of phytoseiid mites observed inside a vine plot and in neighbouring vegetation (other vine plots and uncultivated areas) and (2) dispersal of phytoseiid mites into the plot studied. These data aim to raise some hypotheses concerning natural colonisation of a vineyard by predatory mites. The study was carried out over 3 years (1999, 2000 and 2001) in an experimental plot planted with two cultivars (Grenache and Syrah) and with Sorbus domestica in a framework of agroforestry investigations. Phytoseiid mites were collected in both cultivated and uncultivated areas surrounding the experimental plot, and their dispersal into the plot studied using “aerial” traps. Densities remained quite low compared to previous studies. The main species encountered in the uncultivated areas and in the traps was Typhlodromus phialatus. Despite the low numbers of phytoseiid mites trapped, densities of phytoseiid mites into the vine field increased during 3 years. Typhlodromus phialatus, the species mainly found in the neighbouring uncultivated areas, was rarely found in vineyards. Another morphologically close species was predominant on vines: Typhlodromus exhilaratus. However, Kampimodromus aberrans the main phytoseiid mite species in vineyards of Southern France was not found in the present survey. Hypotheses for this colonisation process are discussed.     

Clinical significance of dust mite allergens

Dust mites are an important cause of allergic diseases worldwide. The traces of Dermatophagoides farinae and Dermatophagoides pteronyssinus can be found all over the world, while Blomia tropicalis are more common allergenic mites in tropical areas. A variety of allergenic components in dust mites have been found, apart from the different positive rates of IgE reactions in dust mite allergic patients, their biological characteristics, effects on the innate immune system, and especially their distribution characteristics in patients are different. Studying the relationship between dust mite allergens and clinical significance will help for diagnosis of patients and formulation of corresponding Allergen Specific Immunotherapy.

     

Aerial dispersal of phytoseiid mites (Acari: Phytoseiidae): estimating falling speed and dispersal distance of adult females

Aerial dispersal is important to immigration and redistribution of phytoseiid mites that often can provide biological control of spider mite pests. Falling speed of a mite and wind largely determine dispersal distance of such a passively blown organism. A diffusion model of wind-blown phytoseiids could provide insight into their dispersal. To this end, we measured body weights and falling speeds of adult females of 13 phytoseiid and one tetranychid mite species. These data were then incorporated into seed dispersal models (Greene and Johnson, Okubo and Levin) and results were compared to mite dispersal distances in wind tunnel, greenhouse and field. Weights of phytoseiid species ranged from 5.25 to 2l.7 μg; starved mites weighed less than fed mites. Geometric diameters ( d _g ) of idiosomas were correlated to weights. Falling speeds for phytoseiids were 0.39–0.73 m/s, and less than for T. urticae (0.79 m/s) in still air. In some species, active mites had slower falling speeds than inactive (anesthetized) mites indicating that behavior may influence falling. Starved mites had significantly slower falling speeds than fed mites and dispersed farther. Equation-based estimates of falling speed were close to measured ones (2–8% deviation) for some species. There were significant relationships between falling speed and body weight and morphological traits. Greene and Johnson's seed dispersal model provided better fits to dispersal of mites in the wind tunnel, greenhouse and field studies than Okubo and Levin's model. Limits of models in describing mite dispersal distance and applications to IPM are discussed.     

New associations of phoretic mites on <Emphasis Type="Italic">Pityokteines curvidens</Emphasis> (Coleoptera,Curculionidae, Scolytinae)

The species composition and abundance of phoretic mites of the bark beetle Pityokteines curvidens caught in pheromone traps were investigated in Croatia. The P. curvidens trapping programs have been in an experimental phase in Croatia since 2004 as a possible monitoring and control system. The trapping program also permits the opportunity to sample phoretic mites found associated with the beetles. Beetles were caught using Curviwit pheromones in Theysohn traps placed in the Litorić region of Croatia. A total of 12 mite species were recovered, including Schizostethus simulatrix, Dendrolaelaps quadrisetus, Histiostoma piceae, H. cf. varia, Paraleius leontonychus, Pleuronectocelaeno barbara, Tarsonemus minimax, Trichouropoda lamellosa, Uroobovella ipidis, Schwiebea sp., Phauloppia lucorum and Dolicheremaeus dorni. Five species, Pl. barbara, Schwiebea sp., H. cf. varia, Ph. lucorum and Do. dorni, are identified for the first time in association with P. curvidens. These findings increase the number of mite species known to be phoretic on P. curvidens from 11 to 16. The present study also increases the number of known mite associates of Pityokteines spp. from 14 to 18.     

Feather mite abundance varies but symbiotic nature of mite‐host relationship does not differ between two ecologically dissimilar warblers

Feather mites are obligatory ectosymbionts of birds that primarily feed on the oily secretions from the uropygial gland. Feather mite abundance varies within and among host species and has various effects on host condition and fitness, but there is little consensus on factors that drive variation of this symbiotic system. We tested hypotheses regarding how within‐species and among‐species traits explain variation in both (1) mite abundance and (2) relationships between mite abundance and host body condition and components of host fitness (reproductive performance and apparent annual survival). We focused on two closely related (Parulidae), but ecologically distinct, species: Setophaga cerulea (Cerulean Warbler), a canopy dwelling open‐cup nester, and Protonotaria citrea (Prothonotary Warbler), an understory dwelling, cavity nester. We predicted that feather mites would be more abundant on and have a more parasitic relationship with P. citrea, and within P. citrea, females and older individuals would harbor greater mite abundances. We captured, took body measurements, quantified feather mite abundance on individuals’ primaries and rectrices, and monitored individuals and their nests to estimate fitness. Feather mite abundance differed by species, but in the opposite direction of our prediction. There was no relationship between mite abundance and any measure of body condition or fitness for either species or sex (also contrary to our predictions). Our results suggest that species biology and ecological context may influence mite abundance on hosts. However, this pattern does not extend to differential effects of mites on measures of host body condition or fitness.     

Three new species of eriophyoid mites (Acari,Eriophyoidea) associated with Lauraceae in China

In this paper, three new species of eriophyoid mites in the family Eriophyidae associated with Phoebe hunanensis Hand.–Mazz. (Lauraceae), namely Gammaphytoptus striatilobus sp. n., Phyllocoptes setalsolenidion sp. n., and Dechela phoebe sp. n. are described and illustrated. All are vagrants causing no apparent damage to the same host plants.     

Acaricides impair prey location in a predatory phytoseiid mite

The use of predatory mites as the sole management tactic in biological control programmes frequently does not fully and reliably prevents damage of phytophagous mites on plants. Therefore, as an alternative, the integration of predatory mites with acaricides can provide more effective control of phytophagous mites than that of the predators only. However, for such integration, acaricides minimal negative impacts on predatory mites are required. In this study, we evaluated the sublethal effects of three acaricides on the foraging behaviour of Neoseiulus baraki (Athias‐Henriot) (Acari: Phytoseiidae) in a coconut production system. The acaricides were assessed for interference with the location of prey habitat using a Y‐tube olfactometer and for interference with the location of the prey colony within the habitat using a video‐tracking system. In addition to the choice of odour source, the time required and the distance walked to make the choice were assessed. The acaricides tested were abamectin, azadirachtin and fenpyroximate. The predatory mite preferred coconuts infested with the coconut mite Aceria guerreronis Keifer (Acari: Eriophyidae) over uninfested coconuts when not exposed to acaricides. However, when exposed to acaricides, the predator did not distinguish between infested and uninfested fruits. When exposed to abamectin, N. baraki spent more time resting and walked greater distances before making the choice of an odour source. Thus, the acaricides impair the ability of the predatory mite N. baraki to locate a prey habitat and to locate a prey within that habitat. The acaricides differentially affected prey foraging by interfering with odour perception.