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Background: South Downs National Park (SDNP) is UK's most visited National Park, and a focus of tick-borne Lyme disease. The first presumed UK autochthonous cases of tick-borne encephalitis and babesiosis were recorded in 2019-20. SDNP aims to conserve wildlife and encourage recreation, so interventions are needed that reduce hazard without negatively affecting ecosystem health. To be successful these require knowledge of site hazards. Methods: British Deer Society members submitted ticks removed from deer. Key potential intervention sites were selected and six 50 m2 transects drag-sampled per site (mostly twice yearly for 2 years). Ticks were identified in-lab (sex, life stage, species), hazard measured as tick presence, density of ticks (all life stages, DOT), and density of nymphs (DON). Sites and habitat types were analysed for association with hazard. Distribution was mapped by combining our results with records from five other sources. Results: A total of 87 Ixodes ricinus (all but one adults, 82% F) were removed from 14 deer (10 Dama dama; three Capreolus capreolus; one not recorded; tick burden, 1-35) at 12 locations (commonly woodland). Five key potential intervention sites were identified and drag-sampled 2015-16, collecting 623 ticks (238 on-transects): 53.8% nymphs, 42.5% larvae, 3.7% adults (13 M, 10 F). Ticks were present on-transects at all sites: I. ricinus at three (The Mens (TM); Queen Elizabeth Country Park (QECP); Cowdray Estate (CE)), Haemaphysalis punctata at two (Seven Sisters Country Park (SSCP); Ditchling Beacon Nature Reserve (DBNR)). TM had the highest DOT at 30/300 m2 (DON = 30/300 m2), followed by QECP 22/300 m2 (12/300 m2), CE 8/300 m2 (6/300 m2), and SSCP 1/300 m2 (1/300 m2). For I. ricinus, nymphs predominated in spring, larvae in the second half of summer and early autumn. The overall ranking of site hazard held for DON and DOT from both seasonal sampling periods. DBNR was sampled 2016 only (one adult H. punctata collected). Woodland had significantly greater hazard than downland, but ticks were present at all downland sites. I. ricinus has been identified in 33/37 of SDNPs 10 km2 grid squares, Ixodes hexagonus 10/37, H. punctata 7/37, Dermacentor reticulatus 1/37. Conclusions: Mapping shows tick hazard broadly distributed across SDNP. I. ricinus was most common, but H. punctata's seeming range expansion is concerning. Recommendations: management of small heavily visited high hazard plots (QECP); post-visit precaution signage (all sites); repellent impregnated clothing for deerstalkers; flock trials to control H. punctata (SSCP, DBNR). Further research at TM may contribute to knowledge on ecological dynamics underlying infection density and predator re-introduction/protection as public health interventions. Ecological research on H. punctata would aid control. SDNP Authority is ideally placed to link and champion policies to reduce hazard, whilst avoiding or reducing conflict between public health and ecosystem health.

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One of the most impactful pests in several coconut production regions across the world is the coconut mite, Aceria guerreronis Keifer. Scholars can obtain some necessary biogeographic information about coconut mites from studies that explore the geographic patterns of morphological variations and molecular properties among coconut mite populations from various locales. To investigate the geographical origin, ancestral host associations, and colonization history of the mite in Thailand, we obtained DNA sequence data from two mitochondrial (16s and COI) and one nuclear region (ITS) from coconut mite samples originating from 25 populations; additionally, we analyzed the morphological variations in the prodorsal shield and the coxigenital and ventral regions of the mite idiosoma. From the results of experiments using both identification methods, we identified the mite as the coconut mite, A. guerreronis (Acari: Eriophyidae). According to the phylogenetic analysis results of the 25 mite samples, we classified the mites as being closely related to mites found by the authors of a previous report in India. We are the first to report the results of a geometric morphometric analysis and molecular identification of A. guerreronis in Thailand, and our findings support the idea that the mites' origin and invasion history are not well documented, which makes it difficult to apply quarantine procedures and search for biological pest control agents.

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Nonpathogenic bacteria likely play important roles in the biology and vector competence of ticks and other arthropods. Coxiella, a gram-negative gammaproteobacterium, is one of the most commonly reported maternally inherited endosymbionts in ticks and has been associated with over 40 tick species. Species-specific Coxiella-like endosymbionts (CLEs) have been reported in the brown dog tick, Rhipicephalus sanguineus sensu lato (Acari: Ixodidae), throughout the world, while recent research suggests low Coxiella diversity among tick species. We investigated CLE diversity among R. sanguineus s.l. ticks across Arizona. We detected 37 recurrent sequence variants (SVs) of the symbiont, indicating greater diversity in these symbiotic bacteria than previously reported. However, two SVs accounted for the vast majority of 16S rRNA amplicon reads. These two dominant CLEs were both closely related to Candidatus C. mudrowiae, an identified symbiont of Rhipicephalus turanicus ticks. One strain strongly associated with the tropical lineage of R. sanguineus s.l. while the other was found almost exclusively in the temperate lineage, supporting the conclusion that CLEs are primarily vertically transmitted. However, occasional mismatches between tick lineage and symbiont SV indicate that horizontal symbiont transfer may occur, perhaps via cofeeding of ticks from different lineages on the same dog. This study advances our understanding of CLE diversity in Rh. sanguineus s.l.

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Rhipicephalus sanguineus s.l. (Latreille, 1806), the brown dog tick, is the most widely distributed tick species in the world. The two dominant lineages, a temperate group and a tropical group, are recognized as important disease vectors for both dogs and humans. The temperate and tropical lineages overlap in range in some regions of the world, including the southwestern United States, where recent outbreaks of Rocky Mountain spotted fever are linked to R. sanguineus s.l. While it is unclear to what extent they may differ in their capacity to transmit pathogens, finer-scale resolution of temperate and tropical lineage distribution may provide insight into the ecology of these two tick groups and the epidemiology of R. sanguineus s.l.-vectored diseases. Using diagnostic polymerase chain reaction assays, we examined the geospatial trends in R. sanguineus s.l. lineages throughout Arizona. We found the temperate and tropical lineages were well delineated, with some overlap in the eastern part of the state. In one county, tropical and temperate ticks were collected on the same dog host, demonstrating that the two lineages are living in sympatry in some instances and may co-feed on the same host.

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BACKGROUND: Ticks are known as the representatives of hematophagous arachnids. They cause various tick-borne diseases, such as severe fever with thrombocytopenia syndrome (SFTS) and Lyme disease. To understand the mechanism of virus infection caused by ticks, morphology for the anatomical characteristics of crucial organs has been widely studied in acarological fields. The conventional methods used for tick observation have inevitable limitations. Dissection is the standard method to obtain the morphological information, and complex microscopy methods were utilized alternatively. OBJECTIVE: The study goal is to obtain the morphological information of ticks in different growth stages non-invasively. METHODS: Optical coherence tomography (OCT) is employed to acquire structural images of various internal organs without damage for observing the growth process of larva, nymph, and adult in Haemaphysalis longicornis ticks in real-time. RESULTS: Various internal organs, such as salivary glands, rectal sac, genital aperture, and anus, were well-visualized by the OCT enface and cross-sectional images, and the variation in size of these organs in each growth stage was compared quantitatively. CONCLUSIONS: Based on the obtained results, we confirmed the potential feasibility of OCT as a non-destructive real-time tool for morphological studies in acarology. Further research using OCT for acarological applications can include monitoring the growth process of ticks in terms of structural changes and investigating morphological differences between normal and virus-infected tick specimens.

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@#This is the first documentation of parasitic mite, Leptus sp., found on a necrophagous blowfly, Chrysomya villeneuvi collected from a decomposing wild boar carcass placed in Taman Negara (National Park), Kuala Keniam, Pahang, Malaysia. Blowflies around the carcass were captured using an insect net before being examined under a stereomicroscope. Upon microscopic observation, we found a mite attached on the scutellum of C. villeneuvi adult. The mite was carefully removed and preserved in 70% ethanol subsequently. Then, the mite was cleared in lactophenol before being mounted in Hoyer’s medium. The morphological identification of the mite was conducted and Leptus sp. was identified. The species belongs to the phalangii species group and the aldonae species subgroup. This study highlights the new association of Leptus sp. and C. villeneuvi for the first time.

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Burial of a cadaver results in a slower decomposition rate, due to more stable below-ground temperatures and restricted access to necrophagous insects. In such circumstances, analysis of the soil mesofauna, with emphasis on mites (Acari) may be more valuable in time-of-death estimations. The production of volatile organic compounds of cadaveric decay results in changes, especially in the soil pH, which in turn would affect the abundance and diversity of the associated mites. In general, the effects of decomposition and the consequently altered pH levels on the abundance of mites in shallow graves, as well as the effects of fluctuating above-ground environmental parameters (temperature, relative humidity, and precipitation) remain unknown. Here, we found that the decay of three pig cadavers buried in shallow graves (<30 cm below) caused a significant increase in the soil pH throughout decomposition, from neutral to alkaline. Cadaver decay attracted an abundance of mites: with 300 mites collected from the three pig cadavers compared to 129 from the control soil samples at the same depth. Mites rapidly became more abundant in cadaver-associated soils than in control soils after the fresh stage. Increasing soil pH had a positive impact on the abundance of mites in graves and there was a significant interaction between cadaver body temperature and soil pH. Above-ground fluctuations in temperature, relative humidity, and precipitation were found to have no significant direct effect on mite abundance in grave or control soils.

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The Neotropical genus Quadraseta Brennan has 15 valid species associated with small mammals and birds. Quadraseta pazca (Brennan and Jones, 1964) is the type species chosen by Brennan (1970) to describe the genus Quadraseta. This species was originally described parasitizing murids in Argentina and later recorded parasitizing cricetids in two different Brazilian states, Minas Gerais and São Paulo. In this study, we provide a redescription of Q. pazca based on the type series. The following characters separate this species from the others within the genus: palptibia lateral setae branched; adoral setae branched; one pair of clavate trichobothria (si); leg I genu with three solenidia (σ); and the base of microseta (ε) of leg I tarsus is proximal to the base of solenidion (ω). In addition, we also provide new locality and host-association records for this species in Brazil.

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Otobius megnini has been associated with certain clinical conditions in horses in both California and Mexico. A number of cases similar to those described previously have been identified by the author in South Africa. This case report summarises these cases to demonstrate that the clinical condition occurs readily in South Africa and may be increasing in occurrence. The disease has minimal coverage in the literature making it more likely that a veterinarian, unfamiliar with the disease, will miss the diagnosis. The author would like to make veterinarians aware of this as a potential differential diagnosis. This study is a retrospective review of clinical data. Clinical records of patients with similar clinical signs and treatment were reviewed and grouped together as relevant cases for this case report. Ten cases of O. megnini associated neuromuscular dysfunction are reported, suggesting a link between the occurrence of the tick and the clinical condition. Clinical signs include third eyelid prolapse, localised muscle fasciculations, elevated heart rate and limb stamping. Serum chemistry changes commonly show increased aspartate aminotransferase and creatine kinase enzymes activities. The occurrence of the ticks within South Africa and the increasing number of cases presented demonstrate the need for more investigation into the pathophysiology of this condition.

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A new species of flat mite, Cenopalpus umbellatus sp. nov. (Acari: Trombidiformes: Tenuipalpidae) is described and illustrated based on females, males, deutonymphs, protonymphs and larvae. The morphological ontogeny in idiosomal and leg chaetotaxy is briefly described for all stages. Mite specimens were collected from the leaves of Rhaphiolepis indica var. umbellata Makino (Rosaceae), an evergreen shrub native to Japan. An identification key to the world species of Cenopalpus is also provided.

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Oligonychus ilicis (McGregor) (Acari: Tetranychidae), commonly known as the southern red mite, or as the coffee red spider mite in Brazil, is one of the main species of herbivorous mites that causes serious damage to coffee plants (Coffea spp.) and thus negatively affects coffee production. Among the biocontrol agents, predatory mites of the family Phytoseiidae play an important role in many biological control programs worldwide due to their potential as suppressor of mite populations mainly from the family Tetranychidae. One of the phytoseiid mites usually associated with O. ilicis is Euseius concordis (Chant), which often occurs abundantly in the coffee crops of Minas Gerais State, Brazil. This study was conducted to assess the predation potential of E. concordis feeding on the larvae and nymph stages of O. ilicis on coffee plants (Coffea arabica L.). Logistic regression analysis revealed a Holling type II functional response, showing that the number of O. ilicis killed by E. concordis increased gradually as the density of O. ilicis increased. Average daily oviposition also increased with prey densities above 6.3 mites/cm2, indicating that maximum oviposition rate is about 1 egg/day. Results of this study suggest that E. concordis has the potential to reduce O. ilicis populations, and this predatory mite can therefore be considered an important natural enemy of the pest O. ilicis in coffee plantations.

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Abstract Amblyomma nodosum is a Neotropical tick species distributed from Mexico to Argentina, with adult individuals infesting different mammal species, including anteaters (Pilosa: Myrmecophagidae). Few reports in Colombia have recorded this species in departments such as Meta, Tolima and Valle del Cauca. In this paper we describe this species using taxonomic, morphometric and molecular methods after collecting individuals parasitizing collared anteaters (Tamandua tetradactyla) in the departments of Cundinamarca and Tolima. Adult specimens were identified based on current taxonomic keys and different morphometric variables were documented in nonengorged individuals. Also, DNA was extracted for PCR amplification and sequencing of 16S rDNA, COI and ITS2 genes. Phylogenetic trees were built. One hundred and thirty-four adult ticks were collected and identified as Amblyomma nodosum, based on morphological, morphometric, molecular and phylogenetic analyses. This is the first study to report the presence of this tick species in the department of Cundinamarca, using multiple identification approaches, thus expanding its geographical records in Colombia.

Resumo Amblyomma nodosum é uma espécie de carrapato Neotropical distribuída do México à Argentina com indivíduos adultos, infestando diversas espécies de mamíferos, incluindo tamanduás (Pilosa: Myrmecophagidae). Na Colômbia, limitados relatos têm registrado essa espécie em alguns departamentos como Meta, Tolima e Valle del Cauca. Neste trabalho, espécimes foram identificados por meio de métodos taxonômicos, morfométricos e moleculares após serem coletados parasitando indivíduos de tamanduá-mirim (Tamandua tetradactyla) dos departamentos de Cundinamarca e Tolima. Espécimes adultos foram identificados por meio de chaves taxonômicas e diversas variáveis morfométricas foram ristradas em indivíduos não ingurgitados. Além disso, o DNA foi extraído para amplificação pela PCR e por sequenciamento dos genes 16S rDNA, COI e ITS2. Árvores filogenéticas foram construídas. No total, 134 carrapatos adultos foram coletados e identificados como Amblyomma nodosum por meio de análises morfológicas, morfométricas, moleculares e de filogenia. Este é o primeiro estudo que relata, por meio de múltiplas ferramentas de identificação, esta espécie no departamento de Cundinamarca ampliando assim seus registros geográficos na Colômbia.

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Although forensic parasitology remains in its infancy compared with more developed fields like forensic entomology, parasites can be useful forensic indicators. We present the case of an individual who disobeyed animal health legislation and crossed animal quarantine boundaries and two state lines with a cattle tick (Rhipicephalus australis) infested horse. Following recognition of the infestation by animal health officers, the individual asserted that the infestation had occurred either during transport or upon arrival at the site of discovery, and that they had not contravened quarantine legislation. Utilizing ticks as forensic indicators, knowledge of the life cycle and minimum age of ticks on the infested horse indicated that the individual's assertions were false, and that they had in fact transported the tick infested horse from a cattle tick endemic region across state lines and quarantine zones.

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The biology of macrochelid mites might offer new venues for the interpretation of the environmental conditions surrounding human death and decomposition. Three human corpses, one from Sweden and two from Spain, have been analysed for the occurrence of Macrochelidae species. Macrocheles muscaedomesticae (Scopoli) females were associated with a corpse that was found in a popular beach area of southeast Spain. Their arrival coincides with the occurrence of one of their major carrier species, the filth fly Fannia scalaris, the activity of which peaks during mid-summer. Macrocheles glaber (Müller) specimens were collected from a corpse in a shallow grave in a forest in Sweden at the end of summer, concurrent with the arrival of beetles attracted by odours from the corpse. Macrocheles perglaber Filipponi and Pegazzano adults were sampled from a corpse found indoors in the rural surroundings of Granada city, south Spain. The phoretic behaviour of this species is similar to that of M. glaber, but it is more specific to Scarabaeidae and Geotrupidae dung beetles, most of which favour human faeces. Macrocheles muscaedomesticae is known from urban and rural areas and poultry farms, M. glaber from outdoors, particularly the countryside, whereas M. perglaber is known from outdoor, rural, and remote, potentially mountainous locations. Macrocheles muscaedomesticae and M. perglaber are reported for the first time from the Iberian Peninsula. This is the first record of M. perglaber from human remains.

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Parasitism, particularly in concert with other sublethal stressors, may play an important, yet underappreciated role in morbidity and mortality of threatened species. During necropsy of southern sea otters (Enhydra lutra nereis) from California submitted to the Marine Wildlife Veterinary Care and Research Center's Sea Otter Necropsy Program between 1999 and 2017, pathologists occasionally observed nasopulmonary mites infesting the respiratory tracts. Infestation was sometimes accompanied by lesions reflective of mite-associated host tissue damage and respiratory illness. Our objectives were to estimate prevalence of nasopulmonary mites, determine the taxonomic identity of the observed mites, and create a DNA reference for these organisms in southern sea otters as an aid in population management. Using unique morphological characteristics discerned via light and scanning electron microscopy (SEM), we identified the mites as Halarachne halichoeri, a species typically associated with harbor seals (Phoca vitiluna). The 18S, 16S, 28S and ITS1-2 genetic regions were sequenced and submitted to GenBank. We observed H. halichoeri mites in 25.6% (95% CI 19.9-33.4%). of southern sea otters from a subset of necropsies performed between 2012 and 2017. This is the first documentation of H. halichoeri in southern sea otters and is suggestive of parasite exchange between sea otters and harbor seals.

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Ticks expend energy while host-seeking and must consume blood to advance to the next life stage. The energy required for activity is derived from the tick's lipid reserves, a valuable resource that sustains the tick until it finds the next host and can take another bloodmeal. The amount of lipid reserves in an unfed tick has been proposed as an index of tick biological age. Two different methods for aging nymphal blacklegged ticks, Ixodes scapularis Say, were analyzed in this study. To study lipid usage, colony-raised nymphs were held in lab-controlled chambers at 21.0 °C and ≥95% relative humidity, with a photoperiod of 12:12 (L:D) h. Samples of ticks were frozen at -80 °C every 2-3 wk, starting at 12-wk postmolt and continuing until 38-wk postmolt. Lipid reserves were determined indirectly through measurements of "physiological age" that estimate the energy a tick has based on the evaluation of morphometric size ratios of the tick scutum and alloscutum, and quantified directly through chloroform extractions of lipid from individual ticks. Morphometric age ratios and lipid amounts were compared to determine if morphometric measurements accurately estimated a tick's physiological state. Although the morphometric age ratio did correlate significantly with total tick lipid content, the predictive value of the ratio was not reliable; chloroform extraction results showed that lipid amounts declined steadily through the study and more accurately characterized the physiological condition of nymphal I. scapularis. The study of physiological aging of blacklegged ticks may lead to a better understanding of how changing environmental conditions affect tick longevity.

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Abstract Predatory mites that belong to the Phytoseiidae family are one of the main natural enemies of phytophagous mites, thus allowing for their use as a biological control. Phytoseiulus macropilis (Banks, 1904) (Acari: Phytoseiidae) is among the main species of predatory mites used for this purpose. Tetranychus urticae Koch, 1836 (Acari: Tetranychidae) is considered to be one of the most important species of mite pests and has been described as attacking over 1,100 species of plants in 140 families with economic value. The objective of the present study was to investigate, in the laboratory, the reproductive parameters of the predatory mite P. macropilis when fed T. urticae. Experiments were conducted under laboratory conditions at 25 ± 2 °C of temperature, 70 ± 10% RH and 14 hours of photophase. In addition, biological aspects were evaluated and a fertility life table was established. The results of these experiments demonstrated that the longevity of adult female was 27.5 days and adult male was 29.0 days. The population was estimated to increase approximately 27 times (Ro) in mean generation time (T), which was 17.7 days. Lastly, the mite population grew 1.2 times/day (λ) and doubled every 3.7 days (TD).

Resumo Os ácaros predadores pertencentes à família Phytoseiidae constituem um dos principais inimigos naturais de ácaros fitófagos, o que possibilita o seu uso em controle biológico. Entre as principais espécies destaca-se Phytoseiulus macropilis (Banks, 1904) (Acari: Phytoseiidae). O ácaro Tetranychus urticae Koch, 1836 (Acari: Tetranychidae) é considerado uma das espécies de ácaros-praga mais importantes, atacando mais de 1.100 espécies de plantas em 140 famílias de valor econômico. Este trabalho foi realizado com o objetivo de estudar, em laboratório, os parâmetros reprodutivos do ácaro predador P. macropilis, quando alimentado com T. urticae. Os estudos foram conduzidos em laboratório à temperatura de 25 ± 2 °C, 70 ± 10% de UR e 14 horas de fotofase e foram avaliados os aspectos biológicos e confeccionada a tabela de vida de fertilidade. Foi constatada uma longevidade de 27,5 dias para fêmeas adultas e 29,0 dias para machos. A população foi estimada em aumentar aproximadamente 27 vezes (Ro) no período médio de duração de geração (T) que foi de 17,7 dias. A população do ácaro cresceu 1,2vezes/dia (λ) e dobrou a cada 3,7 dias (TD).

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The wheat curl mite, Aceria tosichella Keifer, (WCM) is a global pest of bread wheat that reduces yields significantly. In addition, WCM carries Wheat streak mosaic virus (WSMV, family Potyviridae, genus Tritimovirus), the most significant wheat virus in North America; High Plains wheat mosaic virus (HPWMoV, genus Emaravirus, formerly High plains virus); and Triticum mosaic virus (TriMV, family Potyviridae, genus Poacevirus). Viruses carried by WCM have reduced wheat yields throughout the U.S. Great Plains for >50 yr, with average yield losses of 2-3% and occasional yield losses of 7-10%. Acaricides are ineffective against WCM, and delayed planting of winter wheat is not feasible. Five wheat breeding lines containing Cmc4, a WCM resistance gene from Aegilops tauschii, and Wsm2, a WSMV resistance gene from wheat germplasm CO960293-2 were selected from the breeding process and assessed for phenotypic reaction to WCM feeding, population increase, and the degree of WSMV, HPWMoV, and TriMV infection. Experiments determined that all five lines are resistant to WCM biotype 1 feeding and population increase, and that two breeding lines contain resistance to WSMV, HPWMoV, and TriMV infection as well. These WCM-, WSMV-, HPWMoV-, and TriMV-resistant genotypes can be used improve management of wheat yield losses from WCM-virus complexes.

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The relationship between engorgement weight of female Ixodes scapularis Say and characteristics of offspring was studied using field-collected females fed on rabbits in the laboratory. The number of eggs laid was positively related to maternal engorgement weight in one trial, and larval size (estimated by scutal area) was positively related to maternal engorgement weight in the other. These results suggest a trade-off in number of eggs produced versus average size of offspring, possibly determined during late engorgement. The adults for the two trials were collected from different sites in southern Rhode Island and in different seasons (the fall adults were newly emerged, while the spring adults had presumably lived through the winter), so it is not clear whether these results reflect genetic differences or subtle environmental differences between trials. Percent egg hatch and average fat content of larvae were not related to female engorgement weight. We present a modified method to measure lipid content of pooled larval ticks.

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This study was conducted to investigate the relationship between the number of house dust mites/g dust and different physical and environmental variables. A total of 1,040 house dust samples were collected from houses in Bitlis and Mus Provinces, Turkey, between May 2010 and February 2012. Overall, 751 (72.2%) of dust samples were mite positive. The number of mites/g dust varied between 20 and 1,840 in mite-positive houses. A significant correlation was detected between mean number of mites and altitude of houses, frequency of monthly vacuum cleaning, number of individuals in the household, and relative humidity. No association was found between the number of mites and temperature, type of heating, existence of allergic diseases, age and structure of houses. A maximum number of mites were detected in summer and a minimum number was detected in autumn.

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