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Temperature plays an important role in the growth and development of arthropods, and thus the current trend of climate change will alter their biology and species distribution. We used Chaetodactylus krombeini (Acari: Chaetodactylidae), a cleptoparasitic mite associated with Osmia bees (Hymenoptera: Megachilidae), as a model organism to investigate how temperature affects the development and voltinism of C. krombeini in the eastern United States. The effects of temperature on the stage-specific development of C. krombeini were determined at seven constant temperatures (16.1, 20.2, 24.1, 27.5, 30.0, 32.4 and 37.8°C). Parameters for stage-specific development, such as threshold temperatures and thermal constant, were determined by using empirical models. Results of this study showed that C. krombeini eggs developed successfully to adult at all temperatures tested except 37.8°C. The nonlinear and linear empirical models were applied to describe quantitatively the relationship between temperature and development of each C. krombeini stage. The nonlinear Lactin model estimated optimal temperatures as 31.4, 32.9, 32.6 and 32.5°C for egg, larva, nymph, and egg to adult, respectively. In the linear model, the lower threshold temperatures were estimated to be 9.9, 14.7, 13.0 and 12.4°C for egg, larva, nymph, and egg to adult, respectively. The thermal constant for each stage completion were 61.5, 28.1, 64.8 and 171.1 degree days for egg, larva, nymph, and egg to adult, respectively. Under the future climate scenarios, the number of generations (i.e., voltinism) would increase more likely by 1.5 to 2.0 times by the year of 2100 according to simulation. The findings herein firstly provided comprehensive data on thermal development of C. krombeini and implications for the management of C. krombeini populations under global warming were discussed. *Scientific Article No. 3278 of the West Virginia Agricultural and Forestry Experiment Station, Morgantown, West Virginia.

Phi coefficient directly depends on the frequencies of occurrence of organisms and has been widely used in vegetation ecology to analyse the associations of organisms with site groups, providing a characterization of ecological preference, but its application in soil ecology remains rare. Based on a single field experiment, this study assessed the applicability of phi coefficient in indicating the habitat preferences of soil fauna, through comparing phi coefficient-induced results with those of ordination methods in charactering soil fauna-habitat(factors) relationships. Eight different habitats of soil fauna were implemented by reciprocal transfer of defaunated soil cores between two types of subtropical forests. Canonical correlation analysis (CCorA) showed that ecological patterns of fauna-habitat relationships and inter-fauna taxa relationships expressed, respectively, by phi coefficients and predicted abundances calculated from partial redundancy analysis (RDA), were extremely similar, and a highly significant relationship between the two datasets was observed (Pillai's trace statistic = 1.998, P = 0.007). In addition, highly positive correlations between phi coefficients and predicted abundances for Acari, Collembola, Nematode and Hemiptera were observed using linear regression analysis. Quantitative relationships between habitat preferences and soil chemical variables were also obtained by linear regression, which were analogous to the results displayed in a partial RDA biplot. Our results suggest that phi coefficient could be applicable on a local scale in evaluating habitat preferences of soil fauna at coarse taxonomic levels, and that the phi coefficient-induced information, such as ecological preferences and the associated quantitative relationships with habitat factors, will be largely complementary to the results of ordination methods. The application of phi coefficient in soil ecology may extend our knowledge about habitat preferences and distribution-abundance relationships, which will benefit the understanding of biodistributions and variations in community compositions in the soil. Similar studies in other places and scales apart from our local site will be need for further evaluation of phi coefficient.

Amblyseius orientalis (Ehara) (Acari: Phytoseiidae) is a native predatory mite species in China. It used to be considered as a specialist predator of spider mites. However, recent studies show it also preys on other small arthropod pests, such as Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). Experiments were conducted to investigate (1) prey preference of A. orientalis between Tetranychus cinnabarinus (Boisd.) (Acari: Tetranychidae) and B. tabaci, and (2) development, consumption and life table parameters of A. orientalis when reared on T. cinnabarinus, B. tabaci or a mix of both prey species. When preying on different stages of T. cinnabarinus, A. orientalis preferred protonymphs, whereas when preying on different stages of B. tabaci, A. orientalis preferred eggs. When these two most preferred stages were provided together (T. cinnabarinus protonymphs and B. tabaci eggs), A. orientalis randomly selected its prey. Amblyseius orientalis was able to complete its life cycle on B. tabaci eggs, T. cinnabarinus protonymphs, or a mix of both prey. However, its developmental duration was 53.9% and 30.0% longer when reared on B. tabaci eggs than on T. cinnabarinus and a mix of both prey, respectively. In addition, it produced only a few eggs and its intrinsic rate of increase was negative when reared on B. tabaci eggs, which indicates that B. tabaci is not sufficient to maintain A. orientalis population. The intrinsic rates of increase were 0.16 and 0.23 when A. orientalis was fed on the prey mix and T. cinnabarinus, respectively. These results suggest that although B. tabaci is a poor food resource for A. orientalis in comparison to T. cinnabarinus, A. orientalis is able to sustain its population on a mix of both prey. This predatory mite may thus be a potential biological control agent of B. tabaci when this pest co-occurs with the alternative minor pest T. cinnabarinus.

The predatory mite, Neoseiulus californicus (McGregor, 1954) (Acari: Phytoseiidae) is one of the principal natural enemies of tetranychid mites in several countries, promoting efficient control of those mites in several food and ornamental crops. Pest attacks such as that of the spider mite, Tetranychus urticae Koch, 1836 (Acari: Tetranychidae), is one of the problems faced by farmers, especially in the greenhouse, due to the difficulty of its control with the use of chemicals because of the development of fast resistance making it hard to control it. The objective of this work was to study the life history of the predatory mite N. californicus as a contribution to its mass laboratory rearing, having castor bean plant [Ricinus communis L. (Euphorbiaceae)] pollen as food, for its subsequent use as a natural enemy of T. urticae on a cultivation of greenhouse rosebushes. The studies were carried out in the laboratory, at 25 ± 2°C of temperature, 70 ± 10% RH and a 14 hour photophase. The biological aspects and the fertility life table were appraised. Longevity of 32.9 days was verified for adult females and 40.4 days for males. The intrinsic rate of increase (rm) was 0.2 and the mean generation time (T) was 17.2 days. The population doubled every 4.1 days. The results obtained were similar to those in which the predatory mite N. californicus fed on T. urticae.

Rosacea is a chronic inflammatory condition that affects the skin of the face and the eyes. The aetiology of rosacea is not clearly established but increasing evidence suggests a potential role for bacteria in the induction of the condition. A role for Bacillus oleronius, originally isolated from within a Demodex folliculorum mite, in the aetiology of the condition has been suggested. The aim of the study was to determine whether a correlation existed between the level of sebum and the density of D. folliculorum in the skin of erythematotelangiectatic rosacea patients, and the reactivity of these patients' sera to proteins of B. oleronius. Serum reactivity to the 62 and 83 kDa B. oleronius proteins was found in 82.6 % (62/75) of the rosacea patients and in 26.9 % (14/52) of controls (P = 0.0016). In the group of rosacea patients whose sera reacted to B. oleronius proteins, the level of sebum was statistically lower than in controls (P = 0.01). The density of D. folliculorum on the face of Bacillus positive rosacea patients was statistically higher than controls (P = 0.0001). Rosacea patients demonstrated increased Demodex populations on their faces and reduced sebum levels. Their sera also showed reactivity to B. oleronius proteins, suggesting a potential role for this bacterium in the aetiology of rosacea.

Functional and numerical responses of the predatory mite, Neoseiulus longispinosus (Evans) (Acari: Phytoseiidae) to the red spider mite, Oligonychus coffeae Nietner (Acari: Tetranychidae), infesting tea were determined in a laboratory on leaf discs. Prey consumption increased with increases in temperature and prey density. Handling time decreased and successful attack rate increased with increased temperature. N. longispinosus was more voracious on larvae and nymphs than on adults of O. coffeae. Handling time was higher on adult females than on larvae. Rate of predation leveled off at temperatures greater than 25° C. Functional responses to prey density at six temperatures and to each life stage of O. coffeae approximated the Holling type II model. The oviposition rate increased with prey consumption and temperature. On average, a predator consumed 1.62 adult female prey for every egg it laid. With a fixed number of prey available, predation rate per predator decreased with increased predator density.

Oryctes agamemnon arabicus (Coleoptera: Scarabaeidae) is one of the main pests on date palm trees in the United Arab Emirates (UAE). Two mite species were found associated with this beetle: Sancassania sp. (Acari: Astigmata: Acaridae) and Hypoaspis rhinocerotis Oudemans (Acari: Mesostigmata: Laelapidae). Sancassania deutonymphs (hypopi) were phoretic on O. a. arabicus adults and larvae. However, they were also necromenic, because once the host dies they feed on its carcass. The highest deutonymph load was found in the subelytral space of O. a. arabicus adult. The phoretic and necromenic interactions between Sancassania sp. and O. a. arabicus need to be investigated in more detail. H. rhinocerotis was recorded for the first time in UAE. Its role has not yet been studied in the date palm agricultural ecosystem.

In Benin, the tarsonemid mite Polyphagotarsonemus latus (Banks) (Prostigmata: Tarsonemidae) is a key pest of gboma eggplant Solanum macrocarpon (L.) (Solanales: Solanaceae), a leafy vegetable on which it causes considerable damage to the plants and substantial reduction in yield. Predatory mites in the family Phytoseiidae have been successfully used in the biological control of numerous agricultural pests worldwide. In that respect, a population of the phytoseiid mite Amblyseius swirskii (Athias-Henriot) (Mesostigmata: Phytoseiidae) has been identified as a potential predator of P. latus, and is now a candidate for release against this pest in Benin. The objective of the present study is to determine, through laboratory experiments, the predation rate and life table parameters of A. swirskii when feeding on P. latus or alternative food such as maize pollen. Under laboratory conditions the mean number of P. latus consumed by A. swirskii, and daily oviposition, significantly increased as the number of prey increased. Total development time of A. swirskii was significantly shorter when it fed on P. latus than on maize pollen. Net reproduction rate, intrinsic rate of increase, mean generation time and the finite rate of increase of A. swirskii were were all significantly lower on P. latus than on maize pollen. However, doubling time was significantly higher on maize pollen. This study shows that A. swirskii is a good predator of P. latus, and that maize pollen can efficiently sustain A. swirskii populations when P. latus densities on plants become low. Consequently, A. swirskii can be used for the biological control of the broad mite P. latus on gboma eggplant, and on other solanaceous crops in Benin and elsewhere.

Altogether 445 bats, representing nine species, caught during swarming in the Lodowa Cave in Mount Ciemniak, Western Tatra Mountains, southern Poland, were examined for ectoparasitic mites. In total, 259 spinturnicid (Spinturnix mystacina, S. andegavinus, S. kolenatii, S. plecotinus and S. myoti) and 95 argasid (Carios vespertilionis) mites were collected from seven bat species, Myotis myotis, M. mystacinus, M. brandtii, M. daubentonii, Eptesicus nilssonii, Plecotus auritus, and Vespertilio murinus. There were sex-based differences in the prevalence of mites in some hosts but no differences in their mean intensity and there was no observed relationship between the number of mites and the condition of the bats. The prevalence of mites differed significantly between years in E. nilssonii. The results suggested a very low mite load on swarming bats that had no impact on the body condition of bats.

A 36-yr-old male captive siamang (Symphalangus syndactylus) was evaluated for mange in the form of generalized alopecia, flaky skin, and pruritus of 1 mo duration. Multiple skin scrapings and biopsies revealed high numbers of trombidiiform mites identified as Psorobia (formerly Psorergates) sp. near cercopitheci (Acarina: Psorergatidae) based on morphologic characteristics. Prolonged repetitive treatment with ivermectin killed the mites and resolved the clinical signs. Psorergatid mites should be considered as a cause of dry flaky skin in even long-term captive siamangs or other primates. This is the first record of psorergatid mites from a primate host in the family Hylobatidae.

The prevalence and geographic distribution of the fowl tampan, Argas walkerae Kaiser & Hoogstraal, 1969 was determined in the eastern region of the Eastern Cape Province, South Africa by inspecting two fowl houses in the vicinity of each of 72 randomly selected communal cattle dip-tanks. Tampans were collected from 102 (70.8%) of the 144 fowl houses in the neighbourhood of 57 (79.2%) of the 72 selected dip-tanks, and the localities of the collections were mapped. Argas walkerae was present in fowl houses from the warm coastal regions of the Indian Ocean in the south to the cold and mountainous Drakensberg in the north-east of the Province. Taking into account the probable sensitivity of the sampling method, it is estimated that A. walkerae is likely to be present in fowl houses belonging to between 74 and 84% of communities making use of cattle dip-tanks in the eastern region of the Eastern Cape Province, and that when it is present, between 64 and 75% of fowl houses will be infested. The geographic distribution of A. walkerae seemed to be more strongly associated with the presence of fowls and fowl houses containing raw or processed wood in their structure than with climate.

The well studied trade-off between offspring size and offspring number assumes that offspring fitness increases with increasing per-offspring investment. Where mothers differ genetically or exhibit plastic variation in reproductive effort, there can be variation in per capita investment in offspring, and via this trade-off, variation in fecundity. Variation in per capita investment will affect juvenile performance directly--a classical maternal effect--while variation in fecundity will also affect offspring performance by altering the offsprings' competitive environment. The importance of this trade-off, while a focus of evolutionary research, is not often considered in discussions about population dynamics. Here, we use a factorial experiment to determine what proportion of variation in offspring performance can be ascribed to maternal effects and what proportion to the competitive environment linked to the size-number trade-off. Our results suggest that classical maternal effects are significant, but that in our system, the competitive environment, which is linked to maternal environments by fecundity, can be a far more substantial influence.

A storage mite, Tyrophagus putrescentiae, is recently known to be widely distributed in Korea, being commonly found in house dust, and may, therefore, be allergenically important. The purpose of this study was to develop mass rearing techniques for supplying a large quantity of allergens. The laboratory mouse food powder gave the highest yield, showing 1,251.5-fold increase in number after 10 weeks, and the mixed powder of laboratory mouse food and yeast (1:1) also gave same level of the production (1,203.1-fold increase in week 10). Several different combinations of temperature and relative humidity conditions were compared, and the maximum propagation was obtained at 25 degrees C and 64% RH, showing 960-fold increase in number. When the same amount of culture media was used, the size of the culture container did not significantly influence the quantitative yield of T. putrescentiae mites.