This paper reviews the development of pesticide resistance in Tetranychus cinnabarinus (Boisduval) and studies on the genetics and management of pesticide resistance in China. This mite has developed resistance to at least 25 pesticides in China. It first developed resistance to parathion and demeton. As early as 1962, the level of resistance to demeton in T. cinnabarinus reached 62 times, which resulted in control failure of this mite on cotton in most cotton growing areas in China. The genetics of omethoate-resistance and monocrotophos-resistance in T. cinnabarinus is each controlled by an incompletely dominant gene and the development of resistance is therefore rapid. The developmental time and other life table parameters of T. cinnabarinus are altered when the mite becomes pesticide-resistant: life cycle becomes shorter and reproductive rate becomes greater. This is another reason for the rapid development of pesticide resistance in T. cinnabarinus. Pesticide resistance may be managed by rotational use of pesticides, biological control and other methods.

We present a review of enzymatic, immunological and molecular methods used to distinguish between acarine taxa at all levels, including prey within the bodies of predators. Enzymatic techniques include electrophoretic analyses of enzymatic and isozyme patterns. Immunological methods encompass ELISA and the immunodot approach. Molecular methods comprise RAPD (Random Amplified Polymorphic DNA), use of genetic markers and PCR (the Polymerase Chain Reaction). Problems in using molecular methods include the uneven rate of gene evolution, the utilization of very few primers, the need to use invariant species-specific characters, the risk of contamination and the possibility that by employing different methods the student might obtain different results. A glossary of terms used in molecular reports is attached.

Ixodiphagus wasps (Hymenoptera: Encyrtidae) have been known as parasitoids of ticks since the beginning of the 20th Century. Currently, there are seven recognized species: Ixodiphagus texanus Howard, Ixodiphagus hookeri (Howard), Ixodiphagus mysorensis Mani, Ixodiphagus hirtus Nikolskaya, Ixodiphagus theilerae (Fielder), Ixodiphagus biroi Erdos, and Ixodiphagus sagarensis (Geevarghese). These wasps have been found parasitizing ticks belonging to the genera Ornithodoros, Amblyomma, Dermacentor, Hyalomma, Haemaphysalis, Ixodes, and Rhipicephalus. Parasitism by wasp parasitoids results in direct mortality of the tick hosts and appears to have potential for controlling them. This article reviews the taxonomy, life cycle, seasonality, host range and geographical distribution of these wasps, and their potential application to tick control.

Using methods to evaluate ecological niche breadth and overlap, I studied the host-specificity and the host-selection of 11 species of gamasid mites collected from 25 species of small mammals in western Yunnan, China, Levins' niche breadth was used for host-specificity, while Colwell-Futuyma's niche overlap and a fuzzy clustering analysis were used for host-selection. Of the 11 species of gamasid mites, the host-specificities of Laelaps nuttalli and Laelaps echidninus are the lowest (wide niche breadth), and those of Laelaps algericus and Laelaps chini the highest (narrow niche breadth). Mites with little taxonomic affinity tend to parasitize the same hosts (high niche overlap). Taxonomically close mites, however, tend to choose different species of small mammal hosts (low niche overlap). The results indicate that Levins' niche breadth is an effective method for evaluating host-specificity of gamasid mites and other ectoparasites. That there is an inverse relationship between the closeness of gamasid mites in host-selection suggests that there might be an interspecific competitive mechanism in operation.

The biological and ecological characteristics of Amblyseius nicholsi Ehara et Lee (Acari: Phytoseiidae) were studied. The optimal relative humidity for egg hatching was 75.5–85%. Tests of 11 different plant pollens on the development, survival rate and reproduction of A. nicholsi in the laboratory showed that the mites fed different pollens exhibited different immature survival rates. The developmental times from the egg to adult stage ranged from 4.95 to 6.67 days and reproduction was the greatest for A. nicholsi fed Ricinus communis pollen, which was found to be the best pollen diet for A. nicholsi. This study provided fundamental information for mass-rearing of A. nicholsi and for enhancing the performance of A. nicholsi as a predator of citrus pests. Effects of temperature on development, survival rate and fecundity have been observed. The intrinsic rate of natural increase(r_m), net reproductive rate (R₀), finite rate of increase (λ) and time for population to double at 25°C were 0.182, 28.027, 1.199 and 3.8 respectively. These parameters indicated that A. nicholsi had short developmental time and a reproductive potential capable of building high populations in a short time. The predatory capacity of A. nicholsi on Eotetranychus kankitus showed that it is a useful biocontrol agent against the latter.

Mononychellus tanajoa (Bondar) is an important pest of cassava (Manihot esculenta Crantz) in different parts of Africa and South America. The predaceous phytoseiid Euseius citrifolius Denmark & Muma is commonly found associated with M. tanajoa on cassava in southern Brazil. The present work was conducted to evaluate the suitability of M. tanajoa as a food source for E. citrifolius. The results showed that, although M. tanajoa was not the preferred food item, E. citrifolius could still develop and reproduce on that prey, especially when other food items were also available. This predator seems a promising species to be used for the biological control of M. tanajoa.

Laboratory population life tables of Amblyseius orientalis Ehara were constructed at three different constant temperatures and one natural variable temperature. The intrinsic rate of natural increase (r_m), net reproductive rate (R_o) and the finite rate of increase (λ) reached maximum values at the constant temperature of 25°C and 85% RH: r_m= 0.3246, R₀ = 42.93 and λ = 1.3835. At natural variable temperatures with an average of 26.2°C and 85%RH, its mean generation time (T) was the longest: T = 14.75. It was concluded that temperatures from 25°C to 26°C and relative humidity of 85% are the most suitable conditions for the mass-production of Amblyseius orientalis.

Aponychus corpuzae is a pest of bamboo in Fujian, China. The predatory mite Amblyseius longispinosus was explored as a potential biocontrol agent against Ap. corpuzae in a series of experiments on its predation on Ap. corpuzae. The rate of prey consumption (per predator female) increased linearly with temperature from 1.35 at 15°C to 5.22 at 35°C (the relationship can be described by Y = -1.005 0.185 T; R = 0.96), whereas the rate of oviposition increased with temperature from 0.11 at 15°C to 3.58 at 30°C and then decreased to 2.27 at 35°C [the relationship can be described by Y = 0.141 (T-30)² 43]. The rate of predation increased linearly with prey density within the range of 1–9 prey per leaf (Y = 0.805 0.418 X, R = 0.96) and reached a plateau at the density of 9 prey per leaf, but the rate of oviposition increased linearly with prey density Y = 0.955 0.380 X (R = 0.97). As expected, the number of eggs laid by predators increased linearly with the number of prey they consumed (Y = 0.290 0.423 X; R = 0.93); on average, a predator consumed 1.3–2.5 prey to lay 1.0–1.5 eggs. Functional responses of predator to prey density at five different temperatures (15, 20, 25, 30 and 35°C) and to different active life stages of spider mites (larva, protonymph, deutonymph, adult female and adult male) approximated Holling type II. Amblyseius longispinosus was considered more effective against spider mites at 25°C than at other temperatures. They are most effective against adult female spider mites but least effective against spider mite larvae. With a fixed number of prey available, predation rates per predator decreased with predator density. Aponychus corpuzae adults were observed to show defensive behaviour against predators at high prey densities.

The resistance of different citrus species and varieties to citrus rust mite (Phyllocoptruta oleivora) was evaluated in the laboratory. The results indicated that the pineapple orange (Citrus sinensis), Dancy tangerine (C. reticulata), rough lemon (C. limon) and flying dragon (Poncirus trifoliata) are susceptible to citrus rust mite based on the high reproductive rate, long female longevity and rapid population growth. C. grandis, C. ichangensis and sour orange (C. aurantium) possess strong resistance to citrus rust mite and very low reproductive rates and no rates of mite population growth were observed on these three citrus species. Grapefruits (C. paradisi) belong to the medium-resistant group.

The tea pink mite, Acaphylla theae (Watt) were reared at five temperatures (18°C, 22°C, 26°C, 30°C and 34°C) in the laboratory. Tea (Camellia sinensis O. Ktze), Japanese camellia (Camellia japonica L.) and oiltea camellia (Camellia oleifera Abel.) were tested for host preference of the mite. The durations of the different immature stages, adult's longevity and fecundity under each temperature were observed. Their differences were compared and analyzed. The mite only lived on the leaves of tea. It could not complete the whole génération on either Japanese camellia or oiltea camellia. Most of the mites died when they developed to nymph I, however some mites could grow until nymph II on Japanese camellia. A few eggs hatched on oiltea camellia at 26°C. It is clear that tea is the only suitable host for the tea pink mite and its scientific name should be Acaphylla theae (Watt).

The spatial pattern and its time-series dynamics of Eotetranychus pruni (Oudemans) (EPO) were studied in 1994 on apple trees in Gansu, China. The results showed that the active individuals of EPO were aggregatively distributed as colonies both within tree and among trees and the aggregaion intensity within trees was higher that that between trees. The active mites aggregatively disperse within trees. The time-series dynamics of spatial patterns can be divided into two phases: earlier phase (before June) and later phase (after July). The formula for data transformation x′ = log (x 1) was provided, based on the spatial pattern of EPO.

The dispersal responses of Tetranychus viennensis Zacher were studied when the mite was exposed to various sublethal concentrations of methyl parathion and fenpyroximate on peach under laboratory conditions. The study was conducted under direct exposure of mites to pesticides and exposure to their residues. A significant increase in dispersal of this mite was observed as concentrations of pesticides increased from LC₅ to LC₅₀. At LC₂₅ and LC₅₀, fenpyroximate caused greater dispersal under direct exposure than methyl parathion, but there were no significant differences under exposure to their residues. Walk-off was the predominant mode of dispersal.

A new method, the sticky-plate method (SPM), proposed by the authors, was used in surveying population dynamics of the winter grain mite (WGM), Penthaleus major (Duges). This paper deals with the effects of SPM with reference to the conventional plant by plant count-mite method (CMM). Results showed that the variation in data and population trends obtained by using SPM were consistent with those from CMM. Reliability analysis displayed no significant differences between the results from the two methods on the bases of statistical principles. Therefore it was proved that SPM was suitable for the investigation of population dynamics of WGM. A model for converting results from SPM into ones from CMM, or vice versa, was built.

The mobility of human follicle mites may play an important role in the infestation and transmission of demodicidosis. In order to better understand the mobility of follicle mites and to test some miticides which may be responsible for the alteration of mobility of the mite, a Computer-Aided Microimage Processing and Analysis System (CAMPAS) for assaying the mobility of Demodex folliculorum was developed. The crawling velocity, as an index of mite mobility, showed a bimodal distribution with peaks from 0 to 40 µm/min and from 200 to 260 µm/min. Scarcely any mites with crawling velocity ranging from 80 to 160 µm/min were detected in these experiments. Adults of D. folliculorum showed two different mobility patterns: inactive and active. All mites with crawling velocity more than 200 µm/min were randomly exposed to (1) a mixture of 1% metronidazole plus 1% bezoar, (2) a mixture of 2% metronidazole plus 2% bezoar and (3) D-Hank's solution (as control). Based on the sequential data on the inhibitive effects of metronidazole-bezoar, it is suggested that both medicines are potent chemical inhibitors of the mobility of D. folliculorum.

In this note we report on the seasonal abundance of Abrolophus neobrevicollis Zhang & Goldarazena parasitic on Thrips trehernei Priesner in a meadow located in the Basque Country (Northern Spain). We also provide a list of thrips hosts of A. neobrevicollis and other species ectoparasitic on thrips captured in different habitats in the Basque Country.

The hypothesis that the differences between the effectiveness of larvae of Allothrombium ovatum against Aphis gossypii on cotton but their limited effect on Rhopalosiphum padi on wheat and Myzus persicae are due to mite preference for A. gossypii-cotton is tested in laboratory experiments. Contrary to the prediction of the hypothesis, larvae of A. ovatum showed no significant preference for any leaves when given cotton, wheat and rape in three-choice tests, nor for any aphid species when given A. gossypii, R. padi and Myzus persicae, nor for any aphid-plant association when given A. gossypii on cotton, R. padi on wheat and M. persicae on rape. Observations on population dynamics of mite-aphid on three host plant species showed that larval mite populations were coupled with that of A. gossypii on cotton and R. padi on wheat, but not with M. persicae on rape. Patterns of larval mite interaction of three aphid species in the field are discussed in the light of the results of these experiments.

From 1974 to 1995, a retrospective evaluation was carried out by questionnaire of the systemic adverse reactions caused by pure Dermatophagoides farinae extract produced by Medical Acarology Laboratory, Shanghai Medical University (SMU-Df) during diagnosis and specific immunotherapy (SIT) with patients of asthma and rhinitis sensitive to mites. Of a total of 846,342 injections statistically analysed, 142 systemic adverse reactions were observed with an incidence 1.68/10,000 (CL=1.4-2.0/10,000), involving urticaria 0.82/10,000, severe attack of asthma 0.77/10,000, anaphylactic shock 0.07/10,000 (CL= 1.4-12.0/million), and angioedema 0.02/10,000. The time to onset of systemic reactions of the immediate type was <30 minutes in 32 cases (23%), and 1 and 2 hours in 6 cases each (8%); the time to onset of late response type was 3-48 hours in 23 case (59%) with highest incidence of severe asthmatic attacks; and there were 14 cases (10%) unknown. The systemic reactions occurred during skin tests in 18 subjects (13%), dose increasing phase in 96 cases (67%), dosage maintenance phase in 14 cases (10%), and unknown in 14 cases (10%). Among them, six cases were of anaphylactic shock and none of it causing death after emergency managements. The major cause of manifestation of systemic symptoms was coseasonal treatment when environmental exposure to allergens increased. The second cause was related to dosage errors, involving three subjects (3%) during the first injection overdose. The application of SMU-Df extract in skin tests and SIT of allergic disorders sensitive to mites during 22 years in this country indicated that the efficacy and safety of the extract are comparable to similar Df extract of foreign companies with very low risk of systemic adverse reactions. Selection of patient and medical professionals specially trained for SIT will be the key factors in making treatment successful and safe. SIT is an integral part in the mangement of asthma and rhinitis, and is more effective in children and young adults than later in life. A new phase of SIT—preventive allergy treatment (PAT)—for management of childhood asthma and other allergic disorders is a great challenge for allergologists.

In laboratory experiments, the egg, larva, protonymph and deutonymph, and female adult of the mold mite Tyrophagus putrescentiae were exposed to three atmospheric environments 10%CO₂ 5%O₂ 85%N₂, 16%CO₂ 9%O₂ 75%N₂ and natural atmosphere, at six temperatures of 15°C, 20°C, 25°C, 28°C, 30°C and 32°C. The developmental time and survival rate of each immature stage, and the pre-oviposition period, oviposition period, longevity and fecundity of female adults at each combination of atmospheres and temperatures are given. Statistically significant curves of developmental time and survival rate for the whole immature period, and fecundity in different temperatures and atmosphere conditions are simulated. The results show that controlled atmospheres had an obvious influence on development and reproduction of the mite compared with natural atmosphere, and 10%CO₂ and 5%O₂ had stronger inhibition than 16%CO₂ and 9%O₂. The inhibition was stronger at higher temperatures. The larva was most sensitive to controlled atmosphere, followed by protonymph, deutonymph and egg. The controlled atmosphere made the pre-oviposition period longer, oviposition period shorter, longevity of the female adult shorter and fecundity lower. The pre-oviposition period and longevity of the female adult decreased linearly with the increase of temperature, but oviposition period and fecundity changed like a parabola.

Phytoseius wangii Wu & Ou sp.nov. is described. The horridus species group of Phytoseius now contains two species in China.

This study was conducted in the northwestern region of the State of São Paulo, Brazil, to determine mite species of the family Phytoseiidae in patches of native forest. Fifteen species belonging to five genera were collected on 18 plant species. The most frequent phytoseiids were Euseius citrifolius Denmark & Muma and Amblyseius tunus (DeLeon), collected on 15 and 10 plant species, respectively. The largest diversities of phytoseiids were observed on Mabea fistulifera (Euphorbiacea), Bauhinia sp. (Fabaceae) and Banisteria sp. (Malpighiaceae), with nine, eight and six species, respectively.

A new species, Typhlodromus cuii sp. nov. from Davidia sp. in Yunnan, China, is described. The type specimens are deposited in the Guangdong Institute of Entomology, Guangzhou, China.

Three new species of the genus Daidalotarsonemus are described. Daidalotarsonemus digital sp. nov. was collected in samples of mosses on a tree (Sabina chinensis) in Fujian. Daidalotarsonemus cornutus sp.nov. was found in the bark of the tree (Diospyros oleifera) and in the mosses of S. chinensis in Fujian. Daidalotarsonemus duolamella sp. nov. was collected from a tea tree (Camellia sinensis) in Fujian. Types were deposited in the collection of Plant Protection Research Institute, Fujian Academy of Agricultural Sciences, China.

Erythraeus southcotti Goldarazena & Zhang sp.nov. and Erythraeus preciosus Goldarazena & Zhang sp.nov. are described from larvae parasitic on aphids in Navarra (Northern Spain) and anthocorid bugs in Zaragoza (Aragón, Spain). A key to European species of Erythraeus is provided.

Amphotrombium jenseni Zhang gen. & sp. nov. (Acari: Parasitengona) is described from a larva collected on an adult Fimbriaphis (Homoptera: Aphidae) feeding on Streptopus (Liliaceae) in Linn County, Oregon, USA. Stardand notations for Acariformes designated by F. Grandjean were adapted and applied in the description. A new family, Amphotrombiidae is proposed for accommodating this genus. A key to superfamilies of larval Parasitengona is provided.

Unionicola (Polyatax) lumbaria sp. nov. (Acari: Unionicolidae) is described in the paper. The subgenus is reported for the first time from China. The type specimens are deposited in the Department of Biological Science and Engineering, Nanchang University, China.

A sand mite species collected from hare, Lepus oiostolus in western part of Sichuan province was described as Gahrliepia (Walchia) szechuanica by Teng (1963). This species is characterized by fp=B.B.BBB, fcx= 1.1.2 and elongated pentagonal scutum with all setae slender. A redescription was carried out with supplement and correction.

Literature, diagnosis, distribution and host data on five species of Rhizoglyphus occurring in China are given. Keys for the identification of the species are provided for males and females.

The larva, deutonymph, calyptostasic nymphs and adults of Hirstiella diolii sp. nov. (Acari: Pterygosomatidae) are described from captive specimens of the rhinoceros iguana, Cyclura cornuta Bonnaterre (Reptilia: Iguanidae). A key to species is given for adult females of Hirstiella.

A human case of demodicid blepharitis was misidentified as a nematode Thelazia callipaeda, or “eye worm”, infestation by Faust and reported by Howard and Faust in 1927 and 1928 from a Canadian missionary at Huaxi (West China) University, Chengdu, China. The present author shows that all descriptions of the symptoms with the pathological changes from biopsy identified conform to symptoms of demodicid infestation. Presumably the case was a mixed infestation of Demodex folliculorum and D. brevis. This is the earliest actual scientific record of human demodicosis in China, although the patient was not a Chinese national.