Review of ticks of the order Mesostigmata parasitic on reptiles

A list of the 70 species of Australian ticks; diagnostic guides to and species accounts of Ixodes holocyclus (paralysis tick), Ixodes cornuatus (southern paralysis tick) and Rhipicephalus australis (Australian cattle tick); and consideration of the place of Australia in the evolution of ticks with comments on four controversial ideas

Species of Mycosphaerellaceae and Teratosphaeriaceae represent over 40% of the fungi identified on eucalypt leaves worldwide. These include some important pathogens that mainly cause leaf blight and spot, and result in increasingly negative impacts on global commercial eucalypt industries. Eucalyptus plantations are commonly cultivated in southern China for solid wood and pulp products. However, the species diversity and geographic distribution of Mycosphaerellaceae and Teratosphaeriaceae, associated with diseased plantation Eucalyptus leaves in China, have not been clarified. In this study, we conducted the first systematic surveys and sample collections of Mycosphaerellaceae- and Teratosphaeriaceae-like fungi from diseased plantation Eucalyptus leaves in southern China. In total, 558 isolates were obtained from 59 sampled sites in five provinces. One isolate was isolated from each tree. According to the disease symptoms, conidia morphological characteristics, and DNA sequence comparisons of ITS, tef1 and tub2 gene regions. The 558 isolates were identified as Teratosphaeria epicoccoides (312 isolates; 55.9%) and T. destructans (246 isolates, 44.1%). Both species were widely distributed in the sampled regions in southern China. The genotypes of T. epicoccoides and T. destructans were determined based on ITS, tef1, and tub2 sequences. The results showed that multiple genotypes of each species of T. epicoccoides and T. destructans exist in China. Additionally, isolates with multiple genotypes were obtained in all five sampled provinces. These results suggest that both T. epicoccoides and T. destructans are not clonal. This study proved that both T. epicoccoides and T. destructans are dominant species and widely distributed on diseased Eucalyptus leaves in southern China. The wide geographic distribution and potential high genetic diversity pose challenges for the disease management of Teratosphaeria leaf blight and leaf spot in China.

Unique strain of Crimean-Congo hemorrhagic fever virus, Mali.

Argas (Persicargas) streptopelia , n. sp., is described from laboratory-reared adults, nymphs, and larvae, and from larvae infesting doves, Streptopelia spp., in Cyprus, Egypt, and Sudan, and “birds” in South-West Africa. The persicus-like adults and nymphs have a broadly oval body with lateral cells containing large, setiferous pits. Larvae have a highly distinctive dorsal plate and the body becomes uniquely broadly cordiform during feeding. On 218 northward (spring) migrating Streptopelia turtur subsp. examined in Cyprus in 1969, 34 (15.6%) carried larvae (mean infestation load 17.2 larvae per dove). Larvae attach to the host body and legs, never to the head; thus they were overlooked for many years. From comparing data for larval dropping from living field-collected hosts and for laboratory rearing, it is postulated that the doves taken in Cyprus became infested 1–10 days earlier in their wintering ground in Africa and that many larvae are carried some distance into Eurasia. Free-living populations of A. (P.) streptopelia , have not yet been discovered in Africa or Eurasia, This tick species' wide distribution and parasitism of migrating doves, some of which are viremic, is of much epidemiological interest. The presence of immature stages of the African Hyalomma marginatum rufipes Koch and Amblyomma lepidum Donitz on the same migrating doves in Cyprus adds to the scope of this importance.

The Ixodidae family comprises ticks that are hematophagous ectoparasites and are considered vectors of several hemoparasites from the Anaplasmataceae family and the genus Hepatozoon, Babesia, and Rickettsia. These ectoparasites parasitize domestic and wild animals belonging to several vertebrate groups. Ticks are highly adapted to different biomes and thus possess a wide geographical distribution. In the Brazilian state of Bahia, localized in the Northeast region, there are large rainforest fragments. Studies have rarely been carried out on ticks, and their hemoparasites, that parasitize wild animals in this region. Thus, this study aimed to identify the tick species parasitizing wild animals rescued in rainforest fragments of Bahia and investigate the presence of hemoparasites in tick tissues. During a 2-year period, 238 ticks were collected from 41 wild mammalians, reptiles, and amphibians. These ectoparasites were taxonomically classified according to their morphological characteristics. The ticks identified belonged to five different species from the Ixodidae family: Amblyomma varium, Amblyomma rotundatum, Amblyomma nodosum, Ixodes loricatus, and Rhipicephalus sanguineus. For the first time, an A. rotundatum parasitizing the Mesoclemmys tuberculata turtle was described. PCR assays using DNA extracted from salivary glands or midgut of the ticks were performed to detect specific DNA fragments of hemoparasites from the genus Rickettsia, Ehrlichia, Babesia, Hepatozoon, and from the Anaplasmataceae family. The results showed positive detection of the Rickettsia genus (7.9%), Anaplasmataceae family (15.8%), and Hepatozoon genus (15.8%). Specific DNA from the Ehrlichia and Babesia genera were not detected in these samples. Specific DNA from members of the Anaplasmataceae family was detected in A. varium for the first time. The present work showed that amphibians, reptiles, and mammals from Bahia's Atlantic Forest areparasitized by different tick species, and that these ectoparasites present pathogens in their tissues that impact both humans and animals due to their zoonotic potential.

Usnea is a highly diverse lichen genus, currently including ca. 350 species that are widely distributed from polar to tropical regions. The exceptional plasticity of morphological traits towards environmental parameters causes difficulties in the circumscription of species, and taxonomic revisions are needed, especially in tropical regions. In this taxonomic treatment of Usnea in tropical South America (Bolivia, Brazil, Colombia, Ecuador, incl. the Galapagos Islands, Paraguay, Peru and Venezuela), we identified 51 species, representing ca. half of the total diversity of species occurring in this region. Out of these 51 species, 16 are so far endemic to South America, whereas several species have a wide distribution, sometimes across several continents. Twelve species were newly described and 15 species were newly reported for South America, indicating that the diversity of Neotropical Usnea species is particularly high and that numerous discoveries are yet to be made. In addition to taxonomic studies, the phylogeny of Usnea was investigated using the nuclear ribosomal genes ITS rDNA and nuLSU, as well as two protein-coding genes RPB1 and MCM7. The concatenated dataset revealed that Usnea is subdivided into four highly-supported clades, corresponding to the traditionally circumscribed subgenera Eumitria, Dolichousnea, Neuropogon and Usnea. However, phenotypic characters that have been used to characterize these subgenera are often homoplasious in the phylogeny and a parallel evolution of these characters is suggested. On the other hand, the majority of species described from phenotypic characters are monophyletic in our phylogeny. We conclude that the combinations of phenotypic characters are suitable discriminators for the delimitation of species. On the other hand, most of these characters have evolved several times independently during the diversification of the genus Usnea and are therefore inadequate to describe generic subdivisions.

BackgroundTicks are known to transmit a wide range of diseases, including those caused by bacteria, viruses, and protozoa. The expansion of tick habitats has been intensified in recent years due to various factors such as global warming, alterations in microclimate, and human activities. Consequently, the probability of human exposure to diseases transmitted by ticks has increased, leading to a higher degree of risk associated with such diseases.MethodsIn this study, we conducted a comprehensive review of domestic and international literature databases to determine the current distribution of tick species in Inner Mongolia. Next, we employed the MaxEnt model to analyze vital climatic and environmental factors influencing dominant tick distribution. Subsequently, we predicted the potential suitability areas of these dominant tick species under the near current conditions and the BCC-CSM2.MR model SSP245 scenario for the future periods of 2021–2040, 2041–2060, 2061–2080, and 2081–2100.ResultsOur study revealed the presence of 23 tick species from six genera in Inner Mongolia, including four dominant tick species (Dermacentor nuttalli, Ixodes persulcatus, Dermacentor silvarum, and Hyalomma asiaticum). Dermacentor nuttalli, D. silvarum, and I. persulcatus are predominantly found in regions such as Xilin Gol and Hulunbuir. Temperature seasonality (Bio4), elevation (elev), and precipitation seasonality (Bio15) were the primary variables impacting the distribution of three tick species. In contrast, H. asiaticum is mainly distributed in Alxa and Bayannur and demonstrates heightened sensitivity to precipitation and other climatic factors. Our modeling results suggested that the potential suitability areas of these tick species would experience fluctuations over the four future periods (2021–2040, 2041–2060, 2061–2080, and 2081–2100). Specifically, by 2081–2100, the centroid of suitable habitat for D. nuttalli, H. asiaticum, and I. persulcatus was predicted to shift westward, with new suitability areas emerging in regions such as Chifeng and Xilin Gol. The centroid of suitable habitat for H. asiaticum will move northeastward, and new suitability areas are likely to appear in areas such as Ordos and Bayannur.ConclusionsThis study provided a comprehensive overview of the tick species distribution patterns in Inner Mongolia. Our research has revealed a significant diversity of tick species in the region, exhibiting a wide distribution but with notable regional disparities. Our modeling results suggested that the dominant tick species’ suitable habitats will significantly expand in the future compared to their existing distribution under the near current conditions. Temperature and precipitation are the primary variables influencing these shifts in distribution. These findings can provide a valuable reference for future research on tick distribution and the surveillance of tick-borne diseases in the region.Graphical

Summary 1. Biotic homogenization (BH), a dominant process shaping the response of natural communities to human disturbance, reflects both the expansion of exotic species at large scales and other mechanisms that often operate at smaller scales. 2. Here, we examined the relationship between BH in plant communities and spatio-temporal landscape disturbance (habitat fragmentation and surrounding habitat conversion) at a local scale (1 km²), using data from a standardized monitoring programme in France. We quantified BH using both a spatial partitioning of taxonomic diversity and the average habitat specialization of communities, which informs on functional BH. 3. We observed a positive relationship between local taxonomic diversity and landscape fragmentation or instability. This increase in local taxonomic diversity was, however, paralleled by a decrease in average community specialization in more fragmented landscapes and in more unstable landscapes around forest sites. The decrease in average community specialization suggests that landscape disturbance causes functional BH, but there was limited evidence for concurrent taxonomic BH. 4. Synthesis. Our results show that landscape disturbance is partly responsible for functional BH at small scales via the extirpation of specialist species, with possible consequences for ecosystem functioning. However, this change in community composition is not systematically associated with taxonomic BH. This has direct relevance in designing biodiversity indicators: metrics incorporating species sensitivity to disturbance (such as species specialization to habitat) appear much more reliable than taxonomic diversity for documenting the response of communities to disturbance.

South America was isolated during most of the Cenozoic, and it was home to an endemic fauna. The South American Native Ungulates (SANUs) exhibited high taxonomical, morphological, and ecological diversity and were widely distributed on the continent. However, most SANU fossil records come from high latitudes. This sampling bias challenges the study of their diversity dynamics and biogeography during important tectonic and biotic events, such as the Great American Biotic Interchange, the faunal exchange between North and South America after the formation of the Isthmus of Panama. We describe new SANU remains from the Neogene of the Cocinetas (northern Colombia) and Falcon (northwestern Venezuela) Basins. In the Cocinetas Basin, the middle Miocene fauna of the Castilletes Formation includes Hilarcotherium miyou sp. nov. (Astrapotheriidae), cf. Huilatherium (Leontiniidae), and Lambdaconus cf. L. colombianus (Proterotheriidae). The late Pliocene fauna of the Ware Formation includes a Toxodontinae indet. and the putative oldest record of Camelidae in South America. In the Falcon Basin, the Pliocene/Pleistocene faunas of the Codore and San Gregorio Formations include Falcontoxodon aguilerai gen. et sp. nov. and Proterotheriidae indet. We provide a phylogenetic analysis for Astrapotheriidae and Toxodontidae. The new data document a low-latitude provinciality within some SANU clades (e.g., Astrapotheriidae, Leontiniidae) during the middle Miocene. This contrasts with the wide latitudinal distribution of clades of other mammals recorded in the fauna, including the sparassodont Lycopsis padillai, the sloth Hyperleptus?, and the proterotheriid Lambdaconus cf. L. colombianus. The Pliocene/Pleistocene tropical faunas from northern South America are characterized by the predominance of native taxa despite their proximity to the Isthmus of Panama (fully emerged by that time). Only one North American ungulate herbivore immigrant is present, a cf. Camelidae indet. The Pliocene and early Pleistocene faunas suggest that environmental changes and biotic interactions affected the diversity dynamics and biogeographic patterns of SANUs during the Great American Biotic Interchange.

BackgroundSmall mammals are important maintenance hosts of ectoparasites as well as reservoir hosts for many arthropod-borne pathogens. In Germany, only a few studies have investigated ectoparasite communities on small mammals in their natural habitats. The aim of this study was to assess the species diversity and parameters influencing the mean intensity and prevalence of macroscopically visible ectoparasites, such as fleas, predatory mites and ticks.MethodsA total of 779 small mammals and 3383 ticks were available from earlier investigations for the data analysis of the current study from three differently structured study sites. In addition, fleas and predatory mites were collected from the captured rodents and taxonomically identified. Regression analyses were conducted on the group (ticks/mites/fleas) and species levels using hurdle models for the abundance of ectoparasite groups and a negative binomial model for the abundance of species.ResultsNearly 90% of the small mammals analyzed were infested with ectoparasites, with an average of 7.3 specimens per host. Hosts were infested with up to six species of ectoparasites simultaneously. In total, 12 flea, 11 mite and three tick species were detected. Ticks were more prevalent than fleas or mites, with > 80% of the hosts in urban and forest areas hosting ticks and around 60% of hosts presenting fleas, and only 20–40% of hosts presenting mites. Polyparasitism had a statistically significant influence on the prevalence of the investigated tick, mite and flea species, with odds ratios of > 1.0. Trapping location, season and host characteristics had significant influences on some—but not all—of the investigated species.ConclusionsThe diversity of flea species was unexpectedly high and higher than that reported in comparable studies, which can be explained by the differently structured habitats and regions examined in this study. Polyparasitism was a key influencing factor and had a positive effect on the prevalence and/or abundance of the predominant tick, flea and mite species occurring on small mammals. Season, trapping location, host species and sex of the host species also had an influence on the prevalence and mean intensity of certain, but not all, ectoparasite species.Graphical

BackgroundThe red fox Vulpes vulpes is the most common mesocarnivore in Europe and with a wide geographical distribution and a high density in most terrestrial habitats of the continent. It is fast urbanising species, which can harbor high numbers of different tick species, depending on the region. Here we present the results of a large-scale study, trying to disentangle the intricate relationship between environmental factors and the species composition of ectoparasites in red foxes. The samples were collected in Transylvania (Romania), a region with a diverse geography and high biodiversity. The dead foxes (collected primarily through the National Surveillance Rabies Program) were examined carefully for the presence of ticks.ResultsTicks (n = 4578) were found on 158 foxes (out of 293 examined; 53.9%). Four species were identified: Dermacentor marginatus, Ixodes canisuga, I. hexagonus and I. ricinus. The most common tick species was I. hexagonus (mean prevalence 37.5%, mean intensity 32.2), followed by I. ricinus (15.0%; 4.86), I. canisuga (4.8%; 7.71) and D. marginatus (3.7%; 3.45). Co-occurrence of two or more tick species on the same host was relatively common (12.6%), the most common co-occurrence being I. hexagonus - I. ricinus. For D. marginatus and I. canisuga the highest prevalence was recorded in lowlands, for I. hexagonus in hilly areas, while for I. ricinus in mountains.ConclusionsAltitude influenced the intensity of parasitism, with highest intensity observed for all Ixodes species in hilly areas. Dermacentor marginatus occurred only in lowlands, I. canisuga in lowlands and hilly areas while the other two species occurred in all of the regions studied. Foxes from lower altitudes had the most tick species associated, with most incidences of co-parasitism also recorded here. Land use affected tick-species composition, with the presence of D. marginatus strongly associated with the extension of arable areas and lack of forests. The presence of I. hexagonus was determined only by the extent of arable lands. As foxes are frontrunners of wildlife urbanization process, with a continuous increase of their numbers in urban areas, the knowledge of their ticks’ ecology (and the pathogens vectored by these) is of utmost importance.

A newly described tick species, Amblyomma vikirri, infests two lizard species in the Flinders Ranges of South Australia. Although one of the hosts, Tiliqua rugosa, has a wide distribution, the tick distribution is restricted to a subset of rocky habitats where the other host, Egernia stokesii, lives. Experiments were conducted with unfed ticks, the stage when the tick is waiting for a host and is susceptible to desiccation. Amblyomma vikirri had a significantly stronger preference for rock microhabitats than two other tick species (Aponomma hydrosauri and Amblyomma limbatum) that infest T. rugosa. Unfed Amb. vikirri were also more active than the other two species, and more likely to be in the upper pan of the substrate. At warm temperatures, larvae of Amb. vikirri survived for shorter periods under desiccation stress than larvae of the other two species, although as nymphs Amb. vikirri survived as well or better. The rock crevice microhabitat experienced lower maximum temperatures than other potential, non‐rock refuge sites. The behaviour of Amb. vikirri, its susceptibility to desiccation in the larval stage and the relatively benign conditions in the rock crevices may act together to prevent Amb. vikirri establishing populations beyond rock habitat.

Mini-Editorial Compilation for Special Section

Host body size and the diversity of tick assemblages on Neotropical vertebrates.

Based on a literature review, as well as on our own data, 14 ixodid tick species belonging to 5 genera were registered for the lizard hosts of the genus Lacerta (L. agilis, L. media, and L. strigata) in the Caucasus and the adjacent territories: Haemaphysalis sulcata, Haem. punctata, Haem. parva, Haem. caucasica, Haem. concinna, Haem. inermis, Ixodes ricinus, I. redikorzevi, Dermacentor marginatus, D. reticulatus, Hyalomma marginatum, Rhipicephalus bursa, Rh. rossicum, and Rh. turanicum. Tick species Haem. caucasica were recorded from Armenia for the first time. Our findings of Haem. punctata represent the first record of this species for Chechnya, Ingushetia (Russia), Armenia, and Azerbaijan. Most of the parasite species are associated with L. agilis (13) and L. strigata (12); L. media is a host of 6 tick species. Data on the infestation of Lacerta spp. by four tick species from our material (I. ricinus, Haem. punctata, Haem. caucasica, and Hyal. marginatum) are presented in the article. In addition, our article contains information on the range of infections associated with the above tick species. Castor bean tick I. ricinus (236 specimens), the most represented species in our collection, parasitizes all available terrestrial vertebrates including humans and can be vector of many various pathogens, so our study provides significant epidemiological information.