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PubMed1989

Susceptibility of Ornithodoros parkeri (Cooley) (Acari: Argasidae) and Dermanyssus gallinae (DeGeer) (Acari: Dermanyssidae) to ivermectin.

Ivermectin was injected into hosts and evaluated for effectiveness against the argasid tick Ornithodoros parkeri (Cooley) and the chicken mite Dermanyssus gallinae (DeGeer). O. parkeri second stage nymphs (N2s) showed a marked increase in mortality when fed on mice injected intraperitoneally with ivermectin at a dose between 0.1 and 0.2 mg/kg host body weight. For adult O. parkeri and D. gallinae, 0.4 and 0.5 mg, respectively, per kilogram of host body weight were necessary for an increase in mortality over controls. These latter findings are comparable to those reported for other tick species but differ from those reported for the northern fowl mite, Ornithonyssus sylviarum (Canestrini & Fanzago). Further testing narrowed the effective dose range for O. parkeri adults to between 0.425 and 0.450 mg/kg host body weight. The time interval (4, 8, and 24 h) between ivermectin injection of the host and tick feeding had only a slight influence on the overall effectiveness of the drug. In O. parkeri, doses of 0.0125 to 0.1000 mg/kg body weight did not affect fecundity, hatchability, gross morphology of the reproductive system and synganglion, or histology of the reproductive system. Contrary to reports of irreversibility of effects of ivermectin on gamma aminobutyric acid-mediated neurotransmission, many ivermectin-paralyzed ticks recovered partial mobility over time.

Animals↗
PubMed1995

Rapid house dust mite (Acari: Pyroglyphidae) and storage mite (Acari: Glycyphagidae and Acaridae) allergen test.

Ten years ago a simple technique was described for detecting guanine from house dust mite excretions. The level of guaninine correlated well with the level of house dust mite allergens. Detection of storage mites is becoming more and more important, and these mites also produce guanine. Therefore, the above-mentioned technique provides a good indication of levels of storage mite allergens.

Allergens↗
PubMed2000

Comparative laboratory toxicity of neem pesticides to honey bees (Hymenoptera: Apidae), their mite parasites Varroa jacobsoni (Acari: Varroidae) and Acarapis woodi (Acari: Tarsonemidae), and brood pathogens Paenibacillus larvae and Ascophaera apis.

Laboratory bioassays were conducted to evaluate neem oil and neem extract for the management of key honey bee (Apis mellifera L.) pests. Neem pesticides inhibited the growth of Paenibacillus larvae (Ash, Priest & Collins) in vitro but had no effect on the growth of Ascophaera apis (Olive & Spiltoir). Azadirachtin-rich extract (neem-aza) was 10 times more potent than crude neem oil (neem oil) against P. larvae suggesting that azadirachtin is a main antibiotic component in neem. Neem-aza, however, was ineffective at controlling the honey bee mite parasites Varroa jacobsoni (Ouduemans) and Acarapis woodi (Rennie). Honey bees also were deterred from feeding on sucrose syrup containing > 0.01 mg/ml of neem-aza. However, neem oil applied topically to infested bees in the laboratory proved highly effective against both mite species. Approximately 50-90% V. jacobsoni mortality was observed 48 h after treatment with associated bee mortality lower than 10%. Although topically applied neem oil did not result in direct A. woodi mortality, it offered significant protection of bees from infestation by A. woodi. Other vegetable and petroleum-based oils also offered selective control of honey bee mites, suggesting neem oil has both a physical and a toxicological mode of action. Although oils are not as selective as the V. jacobsoni acaricide tau-fluvalinate, they nonetheless hold promise for the simultaneous management of several honey bee pests.

Animals↗
PubMed2000

Field evaluation of neem and canola oil for the selective control of the honey bee (Hymenoptera: Apidae) mite parasites Varroa jacobsoni (Acari: Varroidae) and Acarapis woodi (Acari: Tarsonemidae).

Neem oil, neem extract (neem-aza), and canola oil were evaluated for the management of the honey bee mite parasites Varroa jacobsoni (Oudemans) and Acarapis woodi (Rennie) in field experiments. Spraying neem oil on bees was more effective at controlling V. jacobsoni than feeding oil in a sucrose-based matrix (patty), feeding neem-aza in syrup, or spraying canola oil. Neem oil sprays also protected susceptible bees from A. woodi infestation. Only neem oil provided V. jacobsoni control comparable to the known varroacide formic acid, but it was not as effective as the synthetic product Apistan (tau-fluvalinate). Neem oil was effective only when sprayed six times at 4-d intervals and not when applied three times at 8-d intervals. Neem oil spray treatments had no effect on adult honey bee populations, but treatments reduced the amount of sealed brood in colonies by 50% and caused queen loss at higher doses. Taken together, the results suggest that neem and canola oil show some promise for managing honey bee parasitic mites, but the negative effects of treatments to colonies and the lower efficacy against V. jacobsoni compared with synthetic acaricides may limit their usefulness to beekeepers.

Animals↗
PubMed2002

Comparison of release mechanisms for botanical oils to control Varroa destructor (Acari: Varroidae) and Acarapis woodi (acari: Tarsonemidae) in colonies of honey bees (Hymenoptera: Apidae).

Two major parasitic pests threaten honey bee populations, the external mite Varroa destructor and the internal mite Acarapis woodi (Rennie). Varroa are beginning to develop resistance to the main chemical defense fluvalinate, and alternative control methods are being pursued. Previous studies have shown that botanical oils, especially thymol, can be effective. Six release devices for either thymol or a blend of botanical oils known as Magic 3 were tested in beehives. The release devices were as follows: (1) low density polyethylene (LDPE) sleeves filled with Magic 3, (2) Magic 3-infused florist blocks, (3) thymol infused florist blocks, (4) a canola oil and thymol mixture wick release, (5) a plastic strip coated with calcium carbonate and Magic 3, and (6) an untreated control. There were significant decreases in varroa levels with the use of Magic 3 sleeves, but brood levels also decreased. Tracheal mite levels significantly decreased with the Magic 3 sleeve treatment, the Magic 3 florist block treatment, and the thymol canola wick treatment. A second experiment showed that changing the location of Magic 3 sleeves in the colony did not detrimentally effect brood levels, but also did not effectively control varroa mites.

Animals↗
PubMed2001

Plant species modifies the functional response of Phytoseiulus persimilis (Acari: Phytoseiidae) to Tetranychus urticae (Acari: Tetranychidae): implications for biological control.

The functional response of the predatory mite Phytoseiulus persimilis Athias-Henriot to eggs of its prey, the spider mite Tetranychus urticae Koch was examined on three plant species. Experiments were done to determine whether differences in the functional response on the three plant species were due to the morphological features of the crop directly on the predator or through an effect of the plant species on the prey. The results show that crop morphology is the only factor influencing the predatory ability of P. persimilis on the three plant species. Fewer eggs were eaten on Ceanothus thyrsiflorus var. 'Autumnal Blue', the plant species with hairy leaves, and greater numbers of prey consumed on Choisya ternata, a species with smooth leaves. However, similarly few eggs were eaten on the smooth, but waxy leaved Euonymus japonicus as on Ceanothus thyrsiflorus, demonstrating that morphological characters of leaves other than the possession of hairs and trichomes may affect the rates of predation. The implications of these results for the tritrophic interactions between plant, predator and prey, and the development of suitable biological control strategies are discussed.

Animals↗
PubMed1997

[Allergenicity and specific protein profiles of mange mites Chorioptes bovis, Psoroptes ovis (Acari: Psoroptidae), Saroptes suis and Notoedres cati (Acari: Sarcoptidae) using SDS-PAGE and immunoblotting].

A main point of immunoparasitological research in regard to pest arthropod-infestation is biochemical and immunological characterization of antigens. Precondition of own examinations to the specific protein pattern of mange mites were in quality and amount sufficient antigen preparations in mite extract solutions. For mite separation and antigen refinement field strains of Chorioptes bovis, Psoroptes ovis, Sarcoptes suis and Notoedres cati from definitive host animals cattle, sheep, pig and cat have been used. Parasites were isolated in a migration procedure. After having applicated subepidermally a low dose of mite extract solutions in sensitized animals allergic skin changes (Immediate reaction type 1) became apparent. SDS-PAGE exhibited specific protein patterns of 4 pathogen mite species. For Chorioptes bovis 16, Psoroptes ovis 15, Sarcoptes suis 27, and Notoedres cati 36 fractions have been detected. Proteins are antigens or allergen structures to be found in saliva, faecal output or moulting products of developmental stages and other metabolites of the parasites. Protein components were transferred onto nitrocellulosis. Immunoblotting made fractions with antigen activity visible.

Allergens↗
PubMed2001

Species association among predaceous and phytophagous apple mites (Acari: Eriophyidae, Phytoseiidae, Stigmaeidae, Tetranychidae).

Predator-predator, predator-prey, and prey-prey associations among nine species of mites were studied in a plot of 100 'Red Delicious' apple (Malus pumila Miller) trees from 1990 to 1997. In 1990, seven-year-old trees were inoculated with Panonychus ulmi (Koch), Tetranychus urticae Koch (Acari: Tetranychidae) or both, and sprayed with azinphosmethyl (alone or plus endosulfan), or nothing. The species Zetzellia mali (Ewing) (Acari: Stigmaeidae), Amblyseius andersoni Chant (Acari: Phytoseiidae), Eotetranychus sp., Bryobia rubrioculus (Scheuten) (Acari: Tetranychidae), and Aculus schlechtendali Nalepa (Acari: Eriophyidae) were already present or immigrated into plots, and Galendromus occidentalis (Nesbitt) and Tvphlodromus pyri Scheuten (Acari: Phytoseiidae) were introduced. Yule's V association index was used to measure positive, neutral, or negative interspecific associations for each species pair, because of its robustness with spatially autocorrelated data. We found that pesticide and release treatments did not greatly affect the association results, but there were strong seasonal differences. Predator-predator associations were the strongest and most consistent, showing negative associations in the early and mid seasons, and neutral ones in late season. Negative associations of T pyri with other predators were the strongest, which is consistent with evidence that this mite can detect other predators on a leaf. Predatorprey seasonal associations were mixed, with some positive and others negative, with most significant associations occurring in the mid season. One prey-prey interaction was positive, again in mid season, most likely because of similar habitat preferences.

Animals↗
PubMedDate not supplied

[Influence of acari of house dust in the tiology of infantile asthma].

We have studied 61 children with a previous diagnosis of a possible allergic disease showing clear symptoms in relation to the respiratory system (rhinitis, asthma, etc.). In all cases prick tests were carried out with house-dust extracts Dermatophagoides pteronyssinus, D. farinae, T. putrescentiae, A. siro and A. siro + Cheyletus spp. Commercial extracts (Bencard) were used for the former two; the remainder were prepared from the pure culture of the corresponding acari. The technique followed has been described separately. From the results obtained (see Table I) the following conclusions have been reached: 1. The acari of the Dermatophagoides species particularly D. peteronyssinus) are those mainly responsible for the antigenic capacity of house-dust studied in the geographic area of Barcelona and its surroundings. 2. A similarity but no antigenic identity exists between the antigenic extracts of D. pteronyssinus and D. farinae. 3. The many positive reactions shown by many patients to the various species of acari frequently found in house-dust are due not so much to the antigenic similarity of these acari as to the multiple sensitization or special condition of the individual person. 4. The allergens proceeding from different species of the Tyroglyphidae family, possibly possess a certain antigenic relationship. 5. Finally, it can be asserted that despite the important role played by the acari of the Dermatophagoides species among the different allergenic components of house-dust, it is the remaining acarian fauna present in this dust biocenosis that also has a distinct influence.

Acari↗
PubMed2002

Predatory role of Neoseiulus fallacis (Acari: Phytoseiidae): spatial and temporal dynamics in Washington red raspberry fields.

The seasonal abundance of spider mites and their predator Neoseiulus fallacis (Garman) (Acari: Phytoseiidae) was determined during three consecutive years in Washington State red raspberry fields. Tetranychus urticae Koch (Acari: Tetranychidae), Eotetranychus carpini borealis (Ewing) (Acari: Tetranychidae), and N. fallacis were commonly found in Skagit and Whatcom Counties. E. carpini borealis colonized the fruiting canes earlier in the season than T. urticae. The two phytophages overlapped in midseason, but T. urticae entered diapause earlier than E. carpini borealis and N. fallacis. Densities of N. fallacis increased with increase in spider mite densities. However, the numerical response of the predator was more evident for T. urticae than for E. carpini borealis. Nevertheless, the predator was spatially associated with the two prey species. The spatial and seasonal distribution of N. fallacis in relationship to host plant phenology and prey distribution may influence the effectiveness of this predator as a biological control agent against spider mites in red raspberry. Densities of the predator increased too late to prevent spider mite damage. The predatory role of N. fallacis could be enhanced by introducing or conserving predators that are more tolerant to climatic factors that prevail in and around the cane canopy in the beginning of the season.

Acari↗
PubMed2000

Arrestment response of the predatory mite Amblyseius longispinosus to Schizotetranychus nanjingensis webnests on bamboo leaves (Acari: Phytoseiidae, Tetranychidae).

The response of the predatory mite Amblyseius longispinosus (Acari: Phytoseiidae) to the webnest of the spider mite Schizotetranychus nanjingensis (Acari: Tetranychidae) was examined using two-choice tests in the laboratory. A. longispinosus females were found significantly more often on leaves with webnests than on leaves without webnests and were often observed searching under the webbing. Because spider mites and their eggs were removed from the webnests before experiments, predators responded to stimuli associated with webbing, mite feeding damage and other residues in the webnests.

Animals↗
PubMed2004

The predatory mite Typhlodromus pyri (Acari: Phytoseiidae) causes feeding scars on leaves and fruits of apple.

Typhlodromus pyri Scheuten (Acari: Phytoseiidae) is the most important predator of Panonychus ulmi (Koch) (Acari: Tetranychidae) in orchards and vineyards. It was recently found that adult T. pyri females cause microscopic scars on apple leaves. The present laboratory experiments were carried out to confirm the production of scars on apple leaves and to assess if females cause scars on fruits as well. Scar production on apple leaves and/or fruits was investigated under various nutritional conditions: no food, pollen of Scots pine (Pinus sylvsestris L.) only, nymphs of P. ulmi only, and pollen + prey. Both on leaves and fruits, either offered alone or in combination, feeding scars were produced under all nutritional conditions, but mostly in the 'no food' treatment. The predators consumed significantly more P. ulmi nymphs when offered alone than when offered in combination with pollen. T. pyri laid eggs under all nutritional conditions, but mostly in the 'pollen + prey' treatment and least when no food was offered. T. pyri females caused scars on both leaves and fruits when offered simultaneously, but more on leaves than on fruits. The scars were also bigger on leaves than on fruits in all experiments. T. pyri survived and reproduced on plant material in the absence of other food sources. Whether the scars produced on leaves and fruits harm the quality of fruits or the yield of apple cannot be concluded from the present experiments.

Animals↗
PubMed2005

Development, oviposition, and mortality of Neoseiulus fallacis (Acari: Phytoseiidae) in response to reduced-risk insecticides.

Eight reduced-risk insecticides (acetamiprid, thiamethoxam, imidacloprid, thiacloprid, methoxyfenozide, pyriproxyfen, indoxacarb, and spinosad) and three conventional insecticides (azinphosmethyl, fenpropathrin, and esfenvalerate) were tested against Neoseiulus fallacis (Garman) (Acari: Phytoseiidae), the most abundant predacious mite in North Carolina apple (Malus spp.) orchards. To assess the effect of insecticides on development and mortality of N. fallacis immatures, 12-h-old eggs were individually placed on bean leaf disks previously dipped in insecticide solutions. Tetranychus urticae Koch (Acari: Tetranychidae) females were added as a food source. None of the reduced-risk insecticides significantly affected immature N. fallacis compared with the control; however, the pyrethroids esfenvalerate and fenpropathrin were highly toxic to immatures. To evaluate the effect of insecticides on mortality and oviposition of adult N. fallacis, 7- to 8-d-old females were confined on insecticide-treated bean leaves with Malephora crocea (Aizoaceae) pollen added as a food source. Spinosad resulted in the highest mortality, whereas azinphosmethyl, acetamiprid, fenpropathrin, and imidacloprid were moderately toxic, and mortality from esfenvalerate, indoxacarb, thiacloprid, methoxyfenozide, pyriproxyfen, and thiamethoxam did not differ significantly from the control. Oviposition was affected in a similar manner, with the exception of acetamiprid that did not affect oviposition, and thiamethoxam that reduced oviposition.

Animals↗
PubMed1985

Pheromones and other semiochemicals of the acari.

In contrast to the exceptional diversity of semiochemical-regulated behavior in the insects, chemical communication in the Acari is restricted to a few limited roles. These include clustering, mate-finding processes, host- and food-finding processes, and dispersal. No evidence of pheromones regulating oviposition, necrophoric behavior, recognition of hive mates, or many other processes found in numerous insect groups has been reported in the Acari. Perhaps the most noteworthy feature of acarine pheromones or allomones is the use of the same or similar molecules by many species. Metastriate ixodids use volatile phenols to regulate courtship behavior and, in at least one species, feeding site selection and attachment as well. Argasid ticks use a water- or saline-soluble assembly pheromone, which appears to represent a single type of compound, if not the identical compound in all cases. Acarid mites use terpenoids as alarm pheromones and allomones, while certain phytoseiid and tetranychnid mites use terpene alcohols as arrestant sex pheromones. Another notable feature of acarine pheromones is the use of multicomponent signals to regulate different events in the behavioral process. Thus, two separate sex pheromones are necessary to successfully complete courtship in certain Dermacentor ticks, while three pheromones appear necessary to complete feeding-site selection, attachment, and clasping in certain Amblyomma species. In other cases, a combination of chemical and physiological signals is used to regulate courtship. Although the same or similar compounds may be used for chemical communication, no universal model describes the behavior of all species in an acarine family or order. Species-specific differences in perception of pheromone concentration, molecular composition, aphrodisiacs, and other selective signals facilitate species isolation, even though the initial steps in the behavior are similar in all species. This combination of unity and diversity allows economy in the biosynthesis of semiochemicals without compromising species integrity. In the brief period following the pioneering discoveries of pheromones in ticks (8) and mites (16, 17), evidence of a variety of acarine semiochemicals has been obtained, several pheromones and allomones have been identified, a sex pheromone gland has been described, and considerable effort has been directed to understanding the regulation of pheromone activity. Nevertheless, our knowledge of communication in this large and exceptionally diverse group is meager.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1975

Neurosecretory system of the American Dog Tick, Dermacentor variabilis (Acari: Ixodidae). ii. Distribution of secretory cell types, axonal pathways and putative neurohemal-neuroendocrine associations; comparative histological and anatomical implications.

Histological observations using specialized techniques reveal neurosecretory cells in 18 centers throughout the rind (cortex) of the central nerve mass or synganglion of Dermacentor variabilis. Many cells contribute to complicated networks of neurosecretory pathways and tracts in pre- and post-esophageal portions of the synganglion. The four types of neurohemal-neuroendocrine associations found in Dermacentor resemble structures found in soft ticks (Argasidae) and in other Arachnida, but are more diverse than those described from any other single species. Neurosecretory terminals are distributed diffusely and in two concentrated associations within the perineurium of the synganglion and major peripheral nerves. Terminals are also distributed in the perineurial layers of lateral segmental organs which lie in the general hemocoel at the level of the pedal nerves. A retrocerebral organ complex surrounds the esophagus at its junction with the midgut. The complex includes dorsal and ventro-lateral lobes (containing neurosecretory terminals and intrinsic secretory cells1 and the proventricular (neurohemal) plexus. This plexus seems to be a modified (concentrated) cardioglial association. Cardioglial associations are also formed by the neurosecretory innervation of vascular walls of the dorsal aorta and circulatory sinuses which envelope the synganglion and major peripheral nerves. Inferential considerations of neurosecretory and endocrine interactions in the Acari are based on these anatomical and histological data which also provide the basis for evolutionary considerations of anatomical relationships and specializations in the neurosecretory systems of other Arachnida.

Acari↗
PubMed2006

A novel disease affecting the predatory mite Phytoseiulus persimilis (Acari, Phytoseiidae): 1. Symptoms in adult females.

Adult female Phytoseiulus persimilis Athias-Henriot (Acari, Phytoseiidae) of one of our laboratory populations showed a lower degree of attraction to herbivore-induced plant volatiles than other laboratory populations. We hypothesized earlier that this consistent change in foraging behavior is a symptom of a disease, as it is a contagious phenomenon. Here we describe more symptoms by comparing mated females of this population (non-responding (NR) population) with mated females of other populations that are strongly attracted to herbivore-induced plant volatiles (responding populations). The most apparent characteristic of the NR population was the presence of numerous dorso-ventrally flattened females (76% of all females). These females had a normal size after mating but shrank during adulthood. Independent of their age, shrunken females did not reproduce and died a few days after shrinking. In addition to these profound differences in short term performance, females from the NR-population showed behavioral changes, including a lower degree of attraction to herbivore-induced plant volatiles, a higher tendency to leave a prey-patch and a lower predation rate. Moreover, about half of the live females of the NR-population carried birefringent dumbbell-shaped crystals in the legs whereas live females of a responding population carried crystals only in the lumen of the Malpighian tubules and the rectum. The symptom 'crystals in the legs' was correlated with low reproduction. Energy dispersive X-ray diffraction of these crystals revealed that they contain calcium and phosphorus along with carbon and oxygen. Crystals with comparable elemental compositions and the same characteristic concentric layering are well known in insects, where they are thought to play a major role in detoxification of calcium and heavy metals, and in storage of phosphorus. The fraction of predators carrying a white spot in the distal part of the opisthosoma, due to accumulation of excretory material in the rectum, was the same in both populations. Present results are discussed in the context of mite pathology and biological control.

Acari↗
PubMed2005

A new genus of the Eutrombidiinae Thor, 1935 (Acari: Eutrombidiidae) parasitic on an endemic beetle from the south of Spain.

Alhamitrombium tetraseta n. g., n. sp. (Acari: Eutrombidiidae: Eutrombidiinae) is described from two larvae ectoparasitic on Trymosternus bolivari Mateu (Coleoptera: Carabidae) from Almería, Spain. The new genus is distinguished from Hexathrombium Cooreman, 1944 and Beronium Southcott, 1986 on the basis of details of the coxalae. A key to the genera of larval Hexathrombiini is presented.

Acari↗
PubMed2006

Revision of the genus Galagocheles Fain (Acari: Cheyletidae), parasites of galagos (Primates: Galagonidae).

Galagocheles Fain, 1979 (Acari: Cheyletidae), comprising permanent parasites of African prosimian primates (Galagonidae), is revised. An amended diagnosis of the genus based on characters of adults and immatures is given. The type-species, G. lemuricola (Lawrence, 1948), from Otolemur garnetti (Ogilby) (type-host) and O. crassicaudatus Geoffroy, is redescribed, and G. lawrencei n. sp. is described from Galago senegalensis Geoffroy (type-host) and G. moholi Smith. The new species differs from G. lemuricola by its smaller body size, the obtuse posterior end of the opisthosoma in males, and by fine, nude setae ps3 in females. The systematics of the cheyletid tribe Niheliini and host-parasite associations of its species are briefly discussed. The tribe Criokerontini is included to the tribe Niheliini. It is suggested that the ancestors of the tribe Niheliini were predaceous cheyletids associated with the nests of arboreal mammals, and the association of Nihelia spp. on mongooses (Herpestidae) is the result of the host-switching from some ancient arboreal mammal.

Acari↗