Mites inhabiting nests of wood warbler, Phylloscopus sibilatrix (Aves: Passeriformes), in the Wielkopolska National Park in western Poland.

The wood warbler, Phylloscopus sibilatrix (Aves: Passeriformes), is a well-known model organism for studying bird migration, breeding habitat selection and nest predation. The nest acarofauna of this bird species has not been extensively studied so far. To provide a comprehensive report on mite species inhabiting wood warbler nests and to assess infestation parameters (prevalence, intensity, and abundance) for mite species and orders, we collected 45 nests of this bird species in the Wielkopolska National Park in western Poland. Analyses revealed a huge diversity (198 species) of mites inhabiting wood warbler nests. We found individuals belonging to the Mesostigmata, Trombidiformes and Sarcoptiformes. The Trombidiformes, represented in our study only by the Prostigmata, achieved statistically significantly lower intensity and abundance, compared to representatives of other orders. However, the number of recorded prostigmatid species was high (65). The most common were: Stigmaeus sphagneti (22 nests), Stigmaeus longipilis (16), Eupodes voxencollinus (15), Cunaxa setirostris (14), Stigmaeus pilatus (11), and Linopodes sp. 2 (10). The prevalence of Mesostigmata and Sarcoptiformes was equal, reaching 91.1%. Most of Gamasina (Mesostigmata) species found in this study were more characteristic of the soil environment and forest litter than bird nests, but there was also a typical bird parasite, viz. Ornithonyssus sylviarum. None of the observed species of Uropodina (Mesostigmata) or Oribatida (Sarcoptiformes) was typical for bird nests. Among the Uropodina, the highest parameters of nest infestation were achieved by Oodinychus ovalis, whereas among the Oribatida, they were achieved by Metabelba pulverosa. We discuss the importance of wood warbler nests for mite dispersal, survival and reproduction.

Estimating intrinsic growth rates of arthropods from partial life tables using predatory mites as examples.

The intrinsic rate of natural increase of a population (rm) has been in focus as a key parameter in entomology and acarology. It is considered especially important in studies of predators that are potential biological control agents of fast-growing pests such as mites, whiteflies and thrips. Life-table experiments under controlled laboratory conditions are standard procedures to estimate rm. However, such experiments are often time consuming and may critically depend on the precise assessment of the developmental time and the fecundity rate early in the reproductive phase. Using selected studies of predatory mites with suitable life-table data, we investigated whether and how measurements of growth rates can be simplified. We propose a new method for estimating rm from partial life tables, in which the researcher can choose a level of precision based on a stand-in measure of relative error. Based on this choice, the procedure helps the researcher to decide when a life-table experiment can be terminated. Depending on the chosen precision, significant amounts of experimental time can be saved without seriously compromising the reliability of the estimated growth parameter.

Review: predatory soil mites as biocontrol agents of above- and below-ground plant pests.

Biological pest control is becoming increasingly important for sustainable agriculture. Although many species of natural enemies are already being used commercially, efficient biological control of various pests is still lacking, and there is a need for more biocontrol agents. In this review, we focus on predatory soil mites, their role as natural enemies, and their biocontrol potential, mainly in vegetable and ornamental crops, with an emphasis on greenhouse systems. These predators are still underrepresented in biological control, but have several advantages compared to predators living on above-ground plant parts. For example, predatory soil mites are often easy and affordable to mass rear, as most of them are generalist predators, which also means that they may be used against various pests and can survive periods of pest scarcity by feeding on alternative prey or food. Many of them can also endure unfavourable conditions, making it easier for them to establish in various crops. Based on the current literature, we show that they have potential to control a variety of pests, both in greenhouses and in the field. However, more research is needed to fully understand and appreciate their potential as biocontrol agents. We review and discuss several methods to increase their efficiency, such as supplying them with alternative food and changing soil/litter structure to enable persistence of their populations. We conclude that predatory soil mites deserve more attention in future studies to increase their application in agricultural crops.

Associations between different Laelapidae (Mesostigmata: Dermanyssoidea) mites and small rodents from Lithuania.

Associations between species of Laelapidae (Mesostigmata: Dermanyssoidea) mites and small rodents have been studied insufficiently. The aim of this study was to investigate infestation patterns of small rodent species by laelapid mites at six locations in Lithuania. A total of 728 rodents were snap- and live-trapped in various locations during 2013-2016. Eight rodent species were identified, namely Apodemus flavicollis, Apodemus agrarius, Myodes glareolus, Micromys minutus, Mus musculus, Microtus oeconomus, Microtus arvalis and Microtus agrestis. A total of 343 (47.1%) rodents were found to be infested with up to eight species of parasitic mites from the Laelapidae family (n = 1363): Laelaps agilis, Laelaps hilaris, Hyperlaelaps microti, Haemogamasus nidi, Haemogamasus hirsutus, Eulaelaps stabularis, Hirstionyssus sunci and Myonyssus gigas. The dominant species of mite found on rodents was L. agilis (89.1%), found on 43.4% of all hosts. Abundance and mean intensity of infestation with mites varied among species of hosts and were highest for A. flavicollis. We document new geographical and host records for gamasid mites of eight rodent species in Lithuania.

Morphometric variation of Androlaelaps fahrenholzi (Mesostigmata: Laelapidae) associated with three Sigmodontinae (Rodentia: Cricetidae) from the north of Chile.

Androlaelaps fahrenholzi is a mite with a large distribution and associated with a wide range of hosts. To assess morphometric variation of A. fahrenholzi associated with different host species (Phyllotis xanthopygus and Akodon albiventer, both from Putre, Chile) and localities (Las Chinchillas National Reserve, Fray Jorge National Park, and Llanos de Challe National Park, all in Chile and all from the host Phyllotis darwini), 41 morphological characters of each specimen were measured, and principal component analysis and discriminant analysis were used. Both analyses showed two groups separated for species of rodents. Mites associated with P. xanthopygus are smaller than those of A. albiventer. The analysis by location indicates two groups: group 1 comprises all mites collected from Fray Jorge National Park and Las Chinchillas National Reserve, and group 2 comprises only mites from Llanos de Challe National Park. These results indicate that A. fahrenholzi population can vary between hosts and geographical areas. Molecular analysis would be necessary to validate these results and determine whether they are subspecies or different species.

Attack rate and prey preference of Lasioseius subterraneous and Protogamasellus mica on four nematode species.

Plant parasitic nematodes are common and important global pests, causing over US$150 billion in crop losses across the agricultural sector worldwide. Meloidogyne javanica and Pratylenchus zeae are two of the most damaging plant-parasitic nematodes and there are limited options for their control. We evaluated the potential of a large (Lasioseius subterraneous) and a small (Protogamasellus mica) mesostigmatan mite as biological control agents of plant-parasitic nematodes. We tested the attack rate and reproductive potential of these two mite species on four nematode species: M. javanica (eggs), Pra. zeae (adults) and two microbivorous nematodes, Mesorhabditis sp. and Aphelenchus avenae (adults for both species). Each mite/nematode combination (1 mite:100 nematodes) was tested in six replicate arenas. In a separate trial, each mite species was presented with 50 A. avenae and 50 Pra. zeae in the same arena to determine prey preference. Both mite species significantly reduced the abundance of all nematode species used in the trials when compared to nematode-only controls. Lasioseius subterraneous consumed all available M. javanica eggs within 72 h. The larger mite had a significantly higher overall attack rate than the smaller mite, each consuming an average of 96 and 72 nematodes, respectively, within 72 h. However, both mites had a similar reproductive rate. Protogamasellus mica displayed a positive preference towards the plant parasitic nematode Pra. zeae over the fungal feeding A. avenae whereas L. subterraneous did not display a prey preference. Our results highlight the potential of these two predators to control plant parasitic nematodes, although further trials under field conditions are needed.

Prey-specific impact of cold pre-exposure on kill rate and reproduction.

Temperature influences biological processes of ectotherms including ecological interactions, but interaction strengths may depend on species-specific traits. Furthermore, ectotherms acclimate to prevailing thermal conditions by adjusting physiological parameters, which often implies costs to other fitness-related parameters. Both predators and prey may therefore pay thermal acclimation costs following exposure to suboptimal temperatures. However, these costs may be asymmetrical between predator and prey, and between the predator and different species of concurrent prey. We investigated whether thermal pre-exposure affected subsequent kill rate and predator fitness when foraging on prey that differ in ease of capture, and whether changes were primarily caused by predator or by prey pre-exposure effects. Specifically, we were interested in whether there were interactions between predator pre-exposed temperature and specific prey. Using the mesostigmatid mite Gaeolaelaps aculeifer as a generalist predator and the collembolans Folsomia candida and Protaphorura fimata as prey, we measured the impact of present temperature, predator pre-exposure temperature, prey pre-exposure temperature (all 10 or 20°C), prey species, and all interactions on prey numbers killed, predator eggs produced, and exploitation of killed prey in a full factorial design. Mites killed P. fimata in equal numbers independent of the presence of F. candida, but killed F. candida when P. fimata was absent. Mite kill rate and reproduction were significantly affected by mite pre-exposure temperature and test temperature, but not by prey pre-exposure temperature. Significantly more of the slower prey was killed than of the quicker prey. Importantly, we found significant synergistic negative interaction effects between predator cold pre-exposure and hunting prey of higher agility on predator kill rate and reproduction. Our findings show that the negative effects of cold and cold pre-exposure on kill rate and reproduction may be more severe when predators forage on quick prey. The study implies that predator cold exposure has consequences for specific prey survival following cold due to altered predation pressures, which in nature should influence the specific prey population dynamics and apparent competition outcomes. The findings exemplify how not only current but also preceding conditions affect ecological interactions, and that effect strength depends on the species involved.

Nasal mites (Mesostigmata: Rhinonyssidae) in African penguins (Spheniscus demersus).

Rhinonyssids are obligate haematophagous mites that parasitize the nasal cavity of vertebrates, and occur in a wide range of birds worldwide. Two species of nasal mites are known to occur in penguins: Rhinonyssus sphenisci, which has been recorded from Humboldt and Magellanic penguins (Spheniscus humboldti and S. magellanicus, respectively), and Rhinonyssus schelli, which has been recorded in Adélie and Gentoo penguins (Pygoscelis adeliae and P. papua, respectively). We examined the nasal cavity of African penguins (Spheniscus demersus) that died while under care at a rehabilitation centre (N = 40) or that were found dead at breeding colonies (N = 67). Nasal mites were found in the nasal cavity and/or paranasal of sinuses of 21 penguins, some of which had signs of mild-to-moderate sinusitis. Prevalence was higher in juveniles (29%) and adults (27%) than in chicks (10%). Mean intensity was 5.9 ± 12.9 mites per infected host (range 1-60). The mites presented morphological characteristics that were at times consistent with either R. sphenisci or R. schelli, and therefore we conservatively classified them as 'R. sphenisci sensu lato'. Our morphometric results raise the question of whether the specific status of R. schelli is justified.

Effects of a mulch layer on the assemblage and abundance of mesostigmatan mites and other arthropods in the soil of a sugarcane agro-ecosystem in Australia.

Sugarcane farmers can utilise a soil conservation technique called green cane trash blanketing, a form of mulching that can increase plant productivity through a number of channels, e.g., via altering soil physical, chemical and biological characteristics, and influence soil arthropod assemblages. Predatory mites (Mesostigmata) are important components of soil communities because they can control populations of other soil-dwelling pest species. Our aim was to characterise mulch-influenced predatory Mesostigmata community assemblages in sugarcane soils in Queensland, Australia. We found that application of a mulch layer significantly increased the abundance of Mesostigmata, and oribatid mites and collembolans, in soils. Furthermore, we observed that the assemblages of Mesostigmata in soil covered by mulch were significantly different to those in bare soil; and the assemblages of Mesostigmata changed over time. The assemblages of Mesostigmata, but not Oribatida or collembolans, were significantly different in soil under mulch depending on whether the mulch was freshly laid, or decomposing. Our results show that the use of mulch, specifically the green cane trash blanket, can increase overall microarthropod abundance including Mesostigmata. This is likely due to increased habitat complexity and changing resource availability.

Macrocheles species (Acari: Macrochelidae) associated with human corpses in Europe.

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.

Dynamic associations between Ips sexdentatus (Coleoptera: Scolytinae) and its phoretic mites in a Pinus pinaster forest in northwest Spain.

The relationship between the pine bark beetle Ips sexdentatus and its phoretic mites in a Pinus pinaster forest in northwest Spain was studied during 2014. Four species of mites were collected, three of them from the body of the beetle-Histiostoma ovalis, Dendrolaelaps quadrisetus and Trichouropoda polytricha-the fourth, Cercoleipus coelonotus, was collected from the sediments. The main aims of this study were to explore (1) mite diversity and related parameters, (2) the location on the body of the (male and female) beetle, as well as mite assemblages, and (3) the seasonal dynamic association between mite species and the beetle. Results indicated that the diversity oscillated around 0.71 through the study period and the most dominant, frequent and abundant mite was H. ovalis. Histiostoma ovalis was found attached to almost all parts of the body (mainly on the elytral declivity and ventral thorax), whereas D. quadrisetus was exclusively found under the elytra, and T. polytricha displayed affinity towards the elytral declivity as well as the ventral thorax. None of the mite species displayed any preference for the sex of the beetle and the most frequent mite assemblage was H. ovalis, T. polytricha and D. quadrisetus all together. Maximum abundance of each phoretic mite species was related with each of the flight peaks of the beetle that would indicate that these mite species use phoresy as a primary method of transport for colonizing new food sources.

Mite communities (Acari: Mesostigmata) in young and mature coniferous forests after surface wildfire.

Density, diversity and assemblage structure of Mesostigmata (cohorts Gamasina and Uropodina) were investigated in Scots pine forests differing in forest age (young: 9-40 years and mature: 83-101 years) in which wildfire occurred. This animal group belongs to the dominant acarine predators playing a crucial role in soil food webs and being important as biological control agents. In total, six forests (three within young and three within mature stands) were inspected in Puszcza Knyszynska Forest Complex in May 2015. At each forest area, sampling was done from burned and adjacent control sites with steel cylinders for heat extraction of soil fauna. Data were analyzed statistically with nested ANOVA. We found a significant effect on mite density of both fire and forest age, with more mites in mature forests and control plots. In total, 36 mite taxa were identified. Mite diversity differed significantly between forest ages but not between burned versus control. Our study indicated that all studied forests are characterized by unique mite species and that the mite communities are dominated by different mite species depending on age forest and surface wildfire occurrence. Finally, canonical correspondence analysis ranked the mite assemblages from control mature, through burned young and burned mature, away from the control young.

Northern fowl mite (Ornithonyssus sylviarum) in Sweden.

Haematophagous mites were collected from the vent region and plumage of chickens in six hobby flocks of ornamental breeds in Sweden, one of which included turkeys. Soiled vent skin and feathers, dermatitis, hyperkeratosis, skin necroses and ulcers were observed in 12 necropsied birds from two of the flocks. The mites were identified as the northern fowl mite Ornithonyssus sylviarum (Mesostigmata: Macronyssidae). This was supported by sequence analysis of a 642-bp region in the mitochondrial cytochrome oxidase subunit 1 (COI) gene (COI) in mites collected from five flocks, which showed 97-99% sequence similarity to O. sylviarum by blast analysis. Pairwise sequence comparisons revealed nucleotide variations in the range of 0-2.8%, whereas amino acid sequences were highly conserved. This paper represents one of very few records of O. sylviarum in European poultry, and is the first to report COI sequence data for O. sylviarum from poultry in Europe.

Mites and Ticks (Acari) of Bats (Chiroptera) collected from Bursa and Kütahya Provinces, North-Western of Türkiye.

Objective: A total of 357 specimens belonging to nineteen species of bats collected from Bursa and Kütahya Provinces, Türkiye, were examined for mite ectoparasites. Methods: Related bat species were collected and studied about ectoparasitologically. For this purpose stereo and light microscopic methods used. Bat species, bat number, acari species, acari number and their gender, infected numbers were determined. Results: The bats were found to harbour nine acarid species: Eyndhovenia euryalis, E. myoti, Steatonyssus noctulus, Steatonyssus sp., Ixodes vespertilionis, Dermanyssus sp., Ornithonyssus desultarius, Anchystropus zelebarii and Macronyssus aristippe. Conclusion: To the best of our knowledge, this is the first report of acarids on Rhinolophus euryale and Myotis daubentoni. New area and host records are reported.

Impact of forest disturbance on microarthropod communities depends on underlying ecological gradients and species traits.

Windstorms and salvage logging lead to huge soil disturbance in alpine spruce forests, potentially affecting soil-living arthropods. However, the impacts of forest loss and possible interactions with underlying ecological gradients on soil microarthropod communities remain little known, especially across different environmental conditions. Here we used DNA metabarcoding approach to study wind-induced disturbances on forest communities of springtails and soil mites. In particular, we aimed to test the effect of forest soil disturbance on the abundance, richness, species composition, and functional guilds of microarthropods. We sampled 29 pairs of windfall-forest sites across gradients of elevation, precipitation, aspect and slope, 2 years after a massive windstorm, named Vaia, which hit North-Eastern Italy in October 2018. Our results showed that wind-induced disturbances led to detrimental impacts on soil-living communities. Abundance of microarthropods decreased in windfalls, but with interacting effects with precipitation gradients. Operative Taxonomic Units (OTU) richness strongly decreased in post-disturbance sites, particularly affecting plant-feeder trophic guilds. Furthermore, species composition analyses revealed that communities occurring in post-disturbance sites were different to those in undisturbed forests (i.e., stands without wind damage). However, variables at different spatial scales played different roles depending on the considered taxon. Our study contributes to shed light on the impacts on important, but often neglected arthropod communities after windstorm in spruce forests. Effects of forest disturbance are often mediated by underlying large scale ecological gradients, such as precipitation and topography. Massive impacts of stronger and more frequent windstorms are expected to hit forests in the future; given the response we recorded, mediated by environmental features, forest managers need to take site-specific conservation measures.

Inclusion of juvenile stages improves diversity assessment and adds to our understanding of mite ecology - A case study from mires in Norway.

Arachnid orders, Mesostigmata, Trombidiformes, and Sarcoptiformes, commonly known as 'mites', are abundant in mires, both as adults and as juveniles. However, due to the challenges of identification, the juvenile forms are often excluded from analyses. This is the first study in mires that included all three mite orders identified to the species level, including juvenile instars. We aimed to compare how diversity and the response to ecological variables differed if only the adults (ad) vs. the total number of specimens (ad+juv) are considered. Samples of 20 Sphagnum species (five subgenera) were collected and mites were extracted using Berlese funnels. Overall, nearly 60,000 mites were analyzed; of these Mesostigmata made up 1.87% of the total, Trombidiformes -0.27%, and Sarcoptiformes -97.86%. The study revealed 154 species (33 Mesostigmata, 24 Trombidiformes, and 97 Sarcoptiformes), the highest diversity of mites ever reported from mires. The inclusion of juveniles increased observed species richness by 6%, with 10 species (one Mesostigmata, six Trombidiformes, and three Sarcoptiformes) represented only by juvenile forms. Seventeen species are new to Norway (four Mesostigmata, one Sarcoptiformes, and 12 Trombidiformes, including five undescribed species of Stigmaeidae and Cunaxidae). Four of these were represented in the samples only by juveniles. Including the juveniles explained a greater amount of the variability of Trombidiformes (explanatory variables account for 23.60% for ad, and 73.74% for ad+juv) and Mesostigmata (29.23% - ad, 52.91% - ad+juv), but had less of an impact for Sarcoptiformes (38.48% - ad, 39.26% - ad+juv). Locality, Sphagnum subgenus and species, wetness, and trophic state significantly affected the mite communities and should be taken into consideration when studying mires. Since juvenile stages contribute significantly to mite diversity in mires, they should also be included in mite studies in other habitats.

Population dynamics of a poultry hematophagous mite: characterization of the population growth and identification of factors of its slowdown using closed mesocosms.

BACKGROUND: A thorough knowledge of the population dynamics of pests and of the main factors affecting population growth is an important prerequisite for the development of effective control strategies. Failures of various treatments aimed at regulating populations of Dermanyssus gallinae are regularly reported in poultry farms and pullulations occur very quickly after first detection. To finely characterize population dynamics of D. gallinae, and to identify the factors modulating population growth, we conducted two successive multi-generation experiments using closed mesocosms equipped with or without automatic counters and housing a host full- or part-time (three nights per week). RESULTS: Population growth was very rapid and the adult to juvenile ratio very different from the prediction by a mathematical model. A male-biased sex ratio was observed in some mesocosms from 21 days and in most mesocosms from 35 days of population growth originating from an inoculum of adult females. A dramatic slowdown in growth was measured in mesocosms equipped with trackers, where the mites' path to the host was constrained. The slowdown in population growth induced by the intermittent presence of the host compared to its full-time presence was much less marked. CONCLUSION: These findings suggest avenues of research for new management methods. They question the relevance of a critical threshold based on traditional trap monitoring to manage D. gallinae. Our results highlight a unique characteristic of D. gallinae that makes it a recalcitrant case to threshold-based practices recommended for integrated pest management (IPM) against other arthropod pests. The dramatic effect of a physical constraint for the mite to access the host (unnatural constrained path) confirms an observation made in 1917 and is a reason to design perches that are less conducive to parasite traffic. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Four new species of Halozercon (Acari: Mesostigmata: Zerconidae) from South Siberia Mountains (Russia) with a key to all known species.

Four new species of zerconid mites of the genus Halozercon are described and illustrated based on material collected from litter and soil in Altai and Tuva mountains, South Siberia, Russia-H. alataus sp. n., H. gryphus sp. n., H. kumir sp. n. and H. aesopi sp. n. Morphological characters for the new Halozercon species are given. A key for all known species of Halozercon is attached.

Diversity of phylogenetic information according to the locus and the taxonomic level: an example from a parasitic mesostigmatid mite genus.

Molecular markers for cladistic analyses may perform differently according to the taxonomic group considered and the historical level under investigation. Here we evaluate the phylogenetic potential of five different markers for resolving evolutionary relationships within the ectoparasitic genus Dermanyssus at the species level, and their ability to address questions about the evolution of specialization. COI provided 9-18% divergence between species (up to 9% within species), 16S rRNA 10-16% (up to 4% within species), ITS1 and 2 2-9% (up to 1% within species) and Tropomyosin intron n 8-20% (up to 6% within species). EF-1alpha revealed different non-orthologous copies within individuals of Dermanyssus and Ornithonyssus. Tropomyosin intron n was shown containing consistent phylogenetic signal at the specific level within Dermanyssus and represents a promising marker for future prospects in phylogenetics of Acari. Phylogenetic analyses revealed that the generalist condition is apomorphic and D. gallinae might represent a complex of hybridized lineages. The split into hirsutus-group and gallinae-group in Dermanyssus does not seem to be appropriate based upon these results and D. longipes appears to be composed of two different entities.

A key to the species of Protogamasellus (Acari: Ascidae), with a new species from the Brazilian Pantanal.

A study of soil mites in the Brazilian Pantanal, southwestern Brazil, has shown the frequent occurrence of the genus Protogamasellus, especially in cultivated land. Three species were found in this study, Protogamasellus mica (Athias-Henriot), Protogamasellus sigillophorus Mineiro, Lindquist Moraes, and a new species, Protogamasellus pantanal n. sp., which is here described. A taxonomic key for the identification of species of the genus was prepared, based on the examination of the type specimens of the new species here described, of specimens of other species found in Brazil in this and previous studies, and on the information found in the literature for other species.