Mites as biological tags of their hosts

Traveler Mites: Population Genetic Structure of the Wing Mites Periglischrus paracaligus (Acari: Mesostigmata: Spinturnicidae)

Wing mites of the genus Periglischrus are ectoparasites exclusively associated with phyllostomid bats. These mites show high host specificity and have been studied to understand the evolutionary history of their bat hosts mainly by using a morphological variation. Through a phylogeographic approach, we analyzed the genetic diversity and population genetic structure of the ectoparasite Periglischrus paracaligus Herrin and Tipton which parasitizes Leptonycteris yerbabuenae Martínez and Villa (lesser long-nosed bat) in Mexico. By the implementation of a multilocus approach, we found that P. paracaligus populations were diverse for haplotype diversity, and had values ranging from 0.5 to 1. No genetic structuring in the P. paracaligus parasites was observed along with the distribution of the host, L. yerbabuenae, in Mexico, nor when populations or regions were compared, but our results revealed a process of historical demographic expansion in all the analyzed markers. We discuss possible scenarios that could explain the lack of population structure in the light of the data analyzed for the parasites and the biology of L. yerbabuenae, such as the interplay between parasite and host traits being responsible for the genetic make-up of parasite populations. We also inferred its phylogenetic position among wing mites parasitizing the two other species of Leptonycteris bats. Long-nosed bats' monophyly helps to explain the observed presence of distinctive clades in the wing mite's phylogeny in specific association with each long-nosed bat host species.

Host conservation through their parasites: molecular surveillance of vector-borne microorganisms in bats using ectoparasitic bat flies

Most vertebrates host a wide variety of haematophagous parasites, which may play an important role in the transmission of vector-borne microorganisms to hosts. Surveillance is usually performed by collecting blood and/or tissue samples from vertebrate hosts. There are multiple methods to obtain samples, which can be stored for decades if properly kept. However, blood sampling is considered an invasive method and may possibly be harmful to the sampled individual. In this study, we investigated the use of ectoparasites as a tool to acquire molecular information about the presence and diversity of infectious microorganism in host populations. We tested the presence of three distinct vector-borne microorganisms in both bat blood and bat flies: Bartonella bacteria, malaria-like Polychromophilus sp. (Apicomplexa), and Trypanosoma sp. (Kinetoplastea). We detected the presence of these microorganisms both in bats and in their bat flies, with the exception of Trypanosoma sp. in South African bat flies. Additionally, we found Bartonella sp. in bat flies from one population in Spain, suggesting its presence in the host population even if not detected in bats. Bartonella and Polychromophilus infection showed the highest prevalence in both bat and bat fly populations. Single, co- and triple infections were also frequently present in both. We highlight the use of haematophagous ectoparasites to study the presence of infectious microorganism in host blood and its use as an alternative, less invasive sampling method.

Bat parasites (Acari, Anoplura, Cestoda, Diptera, Hemiptera, Nematoda, Siphonaptera, Trematoda) in France (1762-2018): a literature review and contribution to a checklist

This paper is a bibliographical survey of records of bat parasites in France (including Corsica) between 1762 and 2018. In total, 237 scientific publications were analysed. They show that bats are infected with a large diversity of endoparasites and ectoparasites. A total of 113 parasite taxa were identified from 27 host species; in addition, six bats were not identified to the species-level. The helminth fauna of bats comprises three species of Cestoda, 15 of Trematoda, and 13 of Nematoda. Acari parasites include 53 species (in addition to 22 invalid species). Finally, insect parasites comprise 13 species of Diptera (bat flies), 12 of Siphonaptera (fleas), 3 of Hemiptera (bugs), and 1 Anoplura species. Bat taxa reported with parasites were Barbastella barbastellus, Eptesicus serotinus, Hypsugo savii, Miniopterus schreibersii, Myotis bechsteinii, M. blythii, M. capaccinii, M. dasycneme, M. daubentonii, M. emarginatus, M. myotis, M. mystacinus, M. nattereri, M. punicus, Nyctalus lasiopterus, N. leisleri, N. noctula, Pipistrellus kuhlii, P. nathusii, P. pipistrellus, Plecotus auritus, P. austriacus, Rhinolophus euryale, R. ferrumequinum, R. hipposideros, R. mehelyi, Tadarida teniotis, Eptesicus sp., Myotis sp., Pipistrellus sp., Plecotus sp., Rhinolophus sp. and the species complex Pipistrellus pipistrellus/kuhlii/nathusii. As regards E. nilssonii, Vespertilio murinus (Particoloured Bat), M. alcathoe, M. escalerai, P. macrobullaris and P. pygmaeus, no records were found. These published field data originated from 72 of the 96 departments in metropolitan France. The most commonly cited were Ardèche, Ariège, Bouches-du-Rhône, Haute-Savoie, Maine-et-Loire, Moselle, Meurthe-et-Moselle, Pyrénées-Orientales, Sarthe, Haute-Corse and Corse-du-Sud.

Presence and diversity of Chlamydiae bacteria in Spinturnix myoti, an ectoparasite of bats

Chlamydia spp. and Chlamydia-like organisms are able to infect vertebrates such as mammals, reptiles and birds, but also arthropods and protozoans. Since they have been detected in bats and bat feces, we expected Chlamydiae bacteria to also be present in the mite Spinturnix myoti, an ectoparasite of mouse-eared bats (Myotis spp.). The prevalence of Chlamydiales in 88 S. myoti was 57.95% and significantly depended on bat host species. In addition, the prevalence was significantly different between bat species living in sympatry or in allopatry. While there was uninterpretable sequencing for 16 samples, eight showed best BLAST hit identities lower than 92.5% and thus corresponded to new family-level lineages according to the established taxonomy cut-off. The four remaining sequences exhibited best BLAST hit identities ranging from 94.2 to 97.4% and were taxonomically assigned to three different family-level lineages, with two of them belonging to the Parachlamydiaceae, one to the Simkaniaceae, and one to the Chlamydiaceae. These results highlighted for the first time the presence of Chlamydia-like organisms and the possible zoonotic origin of Chlamydia sp. in S. myoti ectoparasites of bats, and therefore suggest that these ectoparasites may play a role in maintaining and/or transmitting members of the Chlamydiae phylum within Myotis spp. bat populations. Our results further highlight that the wide diversity of bacteria belonging to the Chlamydiae phylum is largely underestimated.

Review of Mites Found on Various Animal Hosts and at Different Localities in Malaysia

Mite biodiversity and distribution in Malaysia is currently understudied. Most previous works on Malaysian Acari have focused on pest organisms of medical, veterinary, and agricultural concern, with a few recent studies centered on mites in forensic contexts. Previous literatures have targeted collection sites in forest reserves and/or mountains in either Peninsular or Malaysian Borneo, though the state of Sarawak had the least publications related to mite species descriptions despite having the highest number of nature parks of any state in the country. Most publications focused on the three states Selangor, Pahang and Sabah. Most of the mite species reported were from mammals (66.3%), with fewer species from birds (21.7%), arthropods (11.2%), and reptiles (0.8%). We believe that further work on the systematic documentation of mite species throughout Malaysia is necessary as it could generate useful tools, such as the use of mites as biogeographical markers or as forensic indicators. Therefore, this review catalogs mite species that have been documented in or on animal hosts in Malaysia and serves as a foundation for future work.

Phylogeography of a migratory songbird across its Canadian breeding range: Implications for conservation units

The objectives of this study were to describe and evaluate potential drivers of genetic structure in Canadian breeding populations of the Ovenbird, Seiurus aurocapilla. We performed genetic analyses on feather samples of individuals from six study sites using nuclear microsatellites. We also assessed species identity and population genetic structure of quill mites (Acariformes, Syringophilidae). For male Ovenbirds breeding in three study sites, we collected light-level geolocator data to document migratory paths and identify the wintering grounds. We also generated paleohindcast projections from bioclimatic models of Ovenbird distribution to identify potential refugia during the last glacial maximum (LGM, 21,000 years before present) as a factor explaining population genetic structure. Birds breeding in the Cypress Hills (Alberta/Saskatchewan) may be considered a distinct genetic unit, but there was no evidence for genetic differentiation among any other populations. We found relatively strong migratory connectivity in both western and eastern populations, but some evidence of mixing among populations on the wintering grounds. There was also little genetic variation among syringophilid mites from the different Ovenbird populations. These results are consistent with paleohindcast distribution predictions derived from two different global climate models indicating a continuous single LGM refugium, with the possibility of two refugia. Our results suggest that Ovenbird populations breeding in boreal and hemiboreal regions are panmictic, whereas the population breeding in Cypress Hills should be considered a distinct management unit.

What do Pneumocystis organisms tell us about the phylogeography of their hosts? The case of the woodmouse Apodemus sylvaticus in continental Europe and western Mediterranean islands

Pneumocystis fungi represent a highly diversified biological group with numerous species, which display a strong host-specificity suggesting a long co-speciation process. In the present study, the presence and genetic diversity of Pneumocystis organisms was investigated in 203 lung samples from woodmice (Apodemus sylvaticus) collected on western continental Europe and Mediterranean islands. The presence of Pneumocystis DNA was assessed by nested PCR at both large and small mitochondrial subunit (mtLSU and mtSSU) rRNA loci. Direct sequencing of nested PCR products demonstrated a very high variability among woodmouse-derived Pneumocystis organisms with a total number of 30 distinct combined mtLSU and mtSSU sequence types. However, the genetic divergence among these sequence types was very low (up to 3.87%) and the presence of several Pneumocystis species within Apodemus sylvaticus was considered unlikely. The analysis of the genetic structure of woodmouse-derived Pneumocystis revealed two distinct groups. The first one comprised Pneumocystis from woodmice collected in continental Spain, France and Balearic islands. The second one included Pneumocystis from woodmice collected in continental Italy, Corsica and Sicily. These two genetic groups were in accordance with the two lineages currently described within the host species Apodemus sylvaticus. Pneumocystis organisms are emerging as powerful tools for phylogeographic studies in mammals.

Parasite diversity of European Myotis species with special emphasis on Myotis myotis (Microchiroptera, Vespertilionidae) from a typical nursery roost

Background

Bats belong to one of the most species-rich orders within the Mammalia. They show a worldwide distribution, a high degree of ecological diversification as well as a high diversity of associated parasites and pathogens. Despite their prominent and unique role, the knowledge of their parasite-host-relationships as well as the mechanisms of co-evolutionary processes are, partly due to strict conservation regulations, scarce.

Methods

Juvenile specimens of the greater mouse-eared bat (Myotis myotis) from a roosting colony in Gladenbach (Hesse, Germany) were examined for their metazoan endo-and ectoparasite infections and pathogens. Morphometric data were recorded and the individuals were checked for Lyssavirus-specific antigen using a direct immunofluorescence test. For unambiguous species identification, the bats were analysed by cyt-b sequence comparison.

Results

Myotis myotis were parasitized by the six insect and arachnid ectoparasite species, i.e. Ixodes ricinus, Ischnopsyllus octactenus, Ichoronyssus scutatus, Steatonyssus periblepharus, Spinturnix myoti and Cimex dissimilis. Additionally, the nematode Molinostrongylus alatus and the cestode Vampirolepis balsaci were recorded. Each bat was parasitized by at least four species. The parasites showed partially extreme rates of infection, never recorded before, with more than 1,440 parasites per single host. Ichoronyssus scutatus, Steatonyssus periblepharus, Vampirolepis balsaci and Molinostrongylus alatus are recorded for the first time in Germany. A checklist for Europe is presented containing records of 98 parasite species of 14 Myotis species.

Conclusions

The Myotis myotis from Gladenbach (Hesse, Germany) were parasitized by a diverse parasite fauna with high infestation rates. We assume that in juvenile Myotis the number of parasites is generally higher than in adults due to only later acquired immune competence and behavioural adaptations. Our results revealed new insights into parasite fauna of M. myotis and European bats in general. The finding of endoparasitic cyclophyllidean cestodes that have a two-host lifecycle is, considering the stationary behaviour of the juvenile bats, rather unusual and suggests a non-predatory transmission mechanism (e.g. via autoinfection).

A new insight gained from the collated literature was that the European wide composition of the Myotis parasite fauna is dominated by a few specific taxonomic groups in Europe.

How a haemosporidian parasite of bats gets around: the genetic structure of a parasite, vector and host compared

Parasite population structure is often thought to be largely shaped by that of its host. In the case of a parasite with a complex life cycle, two host species, each with their own patterns of demography and migration, spread the parasite. However, the population structure of the parasite is predicted to resemble only that of the most vagile host species. In this study, we tested this prediction in the context of a vector-transmitted parasite. We sampled the haemosporidian parasite Polychromophilus melanipherus across its European range, together with its bat fly vector Nycteribia schmidlii and its host, the bent-winged bat Miniopterus schreibersii. Based on microsatellite analyses, the wingless vector, and not the bat host, was identified as the least structured population and should therefore be considered the most vagile host. Genetic distance matrices were compared for all three species based on a mitochondrial DNA fragment. Both host and vector populations followed an isolation-by-distance pattern across the Mediterranean, but not the parasite. Mantel tests found no correlation between the parasite and either the host or vector populations. We therefore found no support for our hypothesis; the parasite population structure matched neither vector nor host. Instead, we propose a model where the parasite's gene flow is represented by the added effects of host and vector dispersal patterns.

Comparative phylogeography of the plateau zokor (Eospalax baileyi) and its host-associated flea (Neopsylla paranoma) in the Qinghai-Tibet Plateau

Background

Specific host-parasite systems often embody a particular co-distribution phenomenon, in which the parasite’s phylogeographic pattern is dependent on its host. In practice, however, both congruent and incongruent phylogeographic patterns between the host and the parasite have been reported. Here, we compared the population genetics of the plateau zokor (Eospalax baileyi), a subterranean rodent, and its host-associated flea species, Neopsylla paranoma, with an aim to determine whether the two animals share a similar phylogeographic pattern.

Results

We sampled 130 host-parasite pairs from 17 localities in the Qinghai-Tibet Plateau (QTP), China, and sequenced a mitochondrial DNA (mtDNA) segment (~2,500 bp), including the complete COI and COII genes. We also detected 55 zokor and 75 flea haplotypes. AMOVA showed that the percentage of variation among the populations of zokors constituted 97.10%, while the within population variation was only 2.90%; for fleas, the values were 85.68% and 14.32%, respectively. Moreover, the flea Fst (fixation index) values were significantly smaller than in zokor. Although the Fst values between zokors and fleas were significantly and positively correlated (N =105, R =0.439, p =0.000), only a small amount (R²= 0.19) of the flea Fst variations could be explained by the zokor Fst variations. The two animals showed very distinct haplotype network structures from each other while co-phylogenetic analyses were unable to reject the hypothesis of an independence of speciation events.

Conclusions

Zokors and fleas have very distinct population genetic patterns from each other, likely due to the influence of other sympatrically-distributed vertebrates on the transmission of fleas.

Lack of population genetic structure and host specificity in the bat fly, Cyclopodia horsfieldi, across species of Pteropus bats in Southeast Asia

Background

Population-level studies of parasites have the potential to elucidate patterns of host movement and cross-species interactions that are not evident from host genealogy alone. Bat flies are obligate and generally host-specific blood-feeding parasites of bats. Old-World flies in the family Nycteribiidae are entirely wingless and depend on their hosts for long-distance dispersal; their population genetics has been unstudied to date.

Methods

We collected a total of 125 bat flies from three Pteropus species (Pteropus vampyrus, P. hypomelanus, and P. lylei) from eight localities in Malaysia, Cambodia, and Vietnam. We identified specimens morphologically and then sequenced three mitochondrial DNA gene fragments (CoI, CoII, cytB; 1744 basepairs total) from a subset of 45 bat flies. We measured genetic diversity, molecular variance, and population genetic subdivision (F_ST), and used phylogenetic and haplotype network analyses to quantify parasite genetic structure across host species and localities.

Results

All flies were identified as Cyclopodia horsfieldi with the exception of two individuals of Eucampsipoda sundaica. Low levels of population genetic structure were detected between populations of Cyclopodia horsfieldi from across a wide geographic range (~1000 km), and tests for isolation by distance were rejected. AMOVA results support a lack of geographic and host-specific population structure, with molecular variance primarily partitioned within populations. Pairwise F_ST values from flies collected from island populations of Pteropus hypomelanus in East and West Peninsular Malaysia supported predictions based on previous studies of host genetic structure.

Conclusions

The lack of population genetic structure and morphological variation observed in Cyclopodia horsfieldi is most likely due to frequent contact between flying fox species and subsequent high levels of parasite gene flow. Specifically, we suggest that Pteropus vampyrus may facilitate movement of bat flies between the three Pteropus species in the region. We demonstrate the utility of parasite genetics as an additional layer of information to measure host movement and interspecific host contact. These approaches may have wide implications for understanding zoonotic, epizootic, and enzootic disease dynamics. Bat flies may play a role as vectors of disease in bats, and their competence as vectors of bacterial and/or viral pathogens is in need of further investigation.

Parasite epidemiology in a changing world: can molecular phylogeography help us tell the wood from the trees?

SUMMARY Molecular phylogeography has revolutionised our ability to infer past biogeographic events from cross-sectional data on current parasite populations. In ecological parasitology, this approach has been used to address fundamental questions concerning host-parasite co-evolution and geographic patterns of spread, and has raised many technical issues and problems of interpretation. For applied parasitologists, the added complexity inherent in adding population genetic structure to perceived parasite distributions can sometimes seem to cloud rather than clarify approaches to control. In this paper, we use case studies firstly to illustrate the potential extent of cryptic diversity in parasite and parasitoid populations, secondly to consider how anthropogenic influences including movement of domestic animals affect the geographic distribution and host associations of parasite genotypes, and thirdly to explore the applied relevance of these processes to parasites of socio-economic importance. The contribution of phylogeographic approaches to deeper understanding of parasite biology in these cases is assessed. Thus, molecular data on the emerging parasites Angiostrongylus vasorum in dogs and wild canids, and the myiasis-causing flies Lucilia spp. in sheep and Cochliomyia hominovorax in humans, lead to clear implications for control efforts to limit global spread. Broader applications of molecular phylogeography to understanding parasite distributions in an era of rapid global change are also discussed.

Glacial refugia in pathogens: European genetic structure of anther smut pathogens on Silene latifolia and Silene dioica

Climate warming is predicted to increase the frequency of invasions by pathogens and to cause the large-scale redistribution of native host species, with dramatic consequences on the health of domesticated and wild populations of plants and animals. The study of historic range shifts in response to climate change, such as during interglacial cycles, can help in the prediction of the routes and dynamics of infectious diseases during the impending ecosystem changes. Here we studied the population structure in Europe of two Microbotryum species causing anther smut disease on the plants Silene latifolia and Silene dioica. Clustering analyses revealed the existence of genetically distinct groups for the pathogen on S. latifolia, providing a clear-cut example of European phylogeography reflecting recolonization from southern refugia after glaciation. The pathogen genetic structure was congruent with the genetic structure of its host species S. latifolia, suggesting dependence of the migration pathway of the anther smut fungus on its host. The fungus, however, appeared to have persisted in more numerous and smaller refugia than its host and to have experienced fewer events of large-scale dispersal. The anther smut pathogen on S. dioica also showed a strong phylogeographic structure that might be related to more northern glacial refugia. Differences in host ecology probably played a role in these differences in the pathogen population structure. Very high selfing rates were inferred in both fungal species, explaining the low levels of admixture between the genetic clusters. The systems studied here indicate that migration patterns caused by climate change can be expected to include pathogen invasions that follow the redistribution of their host species at continental scales, but also that the recolonization by pathogens is not simply a mirror of their hosts, even for obligate biotrophs, and that the ecology of hosts and pathogen mating systems likely affects recolonization patterns.

Fortuitous infestation or wide host range? The case of Spinturnicidae and their bat hosts: reply to Guiller and Deunff (2010)

Defining the degree of host specificity in host-parasite studies can greatly inform cophylogenetic history. In a recent paper, Guiller and Deunff (2010) cast doubt on some points and conclusions drawn from a cophylogenetic study between European bats and Spinturnicid mites (Bruyndonckx et al., 2009a). Here we answer their criticisms and discuss the notion of specificity in Spinturnicid mites.