Nuclear (18S-28S rRNA) and mitochondrial genome markers of Carios (Carios) vespertilionis (Argasidae) support Carios Latreille, 1796 as a lineage embedded in the Ornithodorinae: re-classification of the Carios sensu Klompen and Oliver (1993) clade into its respective subgenera

Novel Rickettsia and host records for argasid ticks, including Alveonasus cooleyi, on wild mammals in Baja California, Mexico

We conducted surveillance of mammals to investigate their associations with argasid ticks and tick-borne pathogens. During 2021, a total of 20 wild carnivores and 57 lagomorphs were sampled, and 39 argasid ticks belonging to two species were collected. All mammals and ticks were tested by molecular assays to detect Borrelia and Rickettsia infections. Nine ticks identified as Otobius megnini were collected from two coyotes (Canis latrans) and 30 Alveonasus cooleyi (McIvor 1941) were collected from six bobcats (Lynx rufus) and one rabbit (Sylvilagus auduboni). We detected Rickettsia spp. DNA in 21 of the 27 (77.8%) tested Av. cooleyi and none of the O. megnini. No ticks were PCR-positive for borreliae and all mammals were PCR-negative for both pathogen genera. Phylogenetic analysis based on gltA, htrA, and 16 S rRNA targets revealed that all rickettsiae from Av. cooleyi clustered with ancestral group rickettsiae, likely representing a novel species of possibly endosymbiotic Rickettsia. The significance of Av. cooleyi and the newly identified Rickettsia sp. to the health of wildlife is unknown, and further work is indicated to determine whether they may be relevant to public health or carnivore conservation.

Insights from entire mitochondrial genome sequences into the phylogeny of ticks of the genera Haemaphysalis and Archaeocroton with the elevation of the subgenus Alloceraea Schulze, 1919 back to the status of a genus

We used entire mitochondrial (mt) genome sequences (14.5-15 kbp) to resolve the phylogeny of the four main lineages of the Haematobothrion ticks: Alloceraea, Archaeocroton, Bothriocroton and Haemaphysalis. In our phylogenetic trees, Alloceraea was the sister to Archaeocroton sphenodonti, a tick of an archetypal reptile, the tuatara, from New Zealand, to the exclusion of the rest of the species of Haemaphysalis. The mt genomes of all four of the Alloceraea species that have been sequenced so far had a substantial insert, 132-312 bp, between the tRNA-Glu (E) gene and the nad1 gene in their mt genomes. This insert was not found in any of the other eight subgenera of Haemaphysalis. The mt genomes of 13 species of Haemaphysalis from NCBI GenBank were added to the most recent data set on Haemaphysalis and its close relatives to help resolve the phylogeny of Haemaphysalis, including five new subgenera of Haemaphysalis not previously considered by other authors: Allophysalis (structurally primitive), Aboimisalis (structurally primitive), Herpetobia (structurally intermediate), Ornithophysalis (structurally advanced) and Segalia (structurally advanced). We elevated Alloceraea Schulze, 1919 to the status of genus because Alloceraea Schulze, 1919 is phylogenetically distinct from the other subgenera of Haemaphysalis. Moreover, we propose that the subgenus Allophysalis is the sister to the rest of the Haemaphysalis (14 subgenera) and that the 'structurally primitive' subgenera Hoogstraal and Kim comprise early diverging lineages. Our matrices of the pairwise genetic difference (percent) of mt genomes and partial 16S rRNA sequences indicated that the mt genome sequence of Al. kitaokai (gb# OM368280) may not be Al. kitaokai Hoogstraal, 1969 but rather another species of Alloceraea. In a similar way, the mt genome sequence of H. (Herpetobia) nepalensis Hoogstraal, 1962 (gb# NC_064124) was only 2% genetically different to that of H. (Allophysalis) tibetensis Hoogstraal, 1965 (gb# OM368293): this indicates to us that they are the same species. Alloceraea cretacea may be better placed in a genus other than Alloceraea Schulze, 1919. Reptiles may have been the host to the most recent common ancestor of Archaeocroton and Alloceraea.

First records of Secretargas transgariepinus (Argasidae) in Libya and Jordan: corrections of collection records and detection of microorganisms

The primarily bat-associated argasid tick, Secretargas transgariepinus (White, 1846), is a member of the Afrotropical and southern Palaearctic fauna. Probably because of its secretive life style, little is known about this species and records of its collection are scant. Based on morphological revisions of the available specimens, we report new Middle Eastern records for this tick species that had been misidentified as other bat-associated argasid taxa. These specimens are larvae from three localities, and represent the first records of S. transgariepinus from two countries: one larva from Sabratha (Libya) was collected from an unidentified bat species (possibly Eptesicus isabellinus), seven larvae from Azraq-Shishan (Jordan), and 78 larvae from Shamwari (Jordan) were all collected from Otonycteris hemprichii. Twenty larvae from Shamwari were also tested for the presence of both, viral or bacterial microorganisms by PCR. Three ticks were found to be infected with the Murid gammaherpesvirus 68 (MHV-68), one with Borrelia burgdorferi sensu lato, and four with a Rickettsia sp. closely related to Rickettsia slovaca. The findings represent a first evidence for the occurrence of these possible pathogens in S. transgariepinus.

New records of soft ticks (Acari: Argasidae) from caves in Brazil, with a morphological study of Ornithodoros fonsecai and an analysis of the taxonomic status of Antricola inexpectata

In this study, we report soft ticks from bat-inhabiting caves in different areas of Brazil. From 2010 to 2019, we collected 807 tick specimens from nine caves located in four Brazilian states among two biomes. Ticks were morphologically identified as Antricola guglielmonei (282 specimens), Ornithodoros cavernicolous (260 specimens), and Ornithodoros fonsecai (265 specimens). Whereas A. guglielmonei was collected on bat guano in hot caves, O. cavernicolous and O. fonsecai were collected in cracks and crevices on the walls of cold caves, sometimes in the same chamber. Morphological identifications were corroborated by molecular and phylogenetic analyses inferred from tick mitochondrial 16S rRNA gene partial sequences. The sequences of A. guglielmonei, O. cavernicolous and O. fonsecai collected in this study clustered with conspecific GenBank sequences from different localities of Brazil. Remarkably, a clade containing 12 sequences of O. fonsecai was clearly bifurcated, denoting a degree of genetic divergence (up to 5 %) of specimens from Cerrado/Atlantic Forest biomes with the specimens from the Caatinga biome. To further evaluate this divergence, we performed morphometric analysis of the larval stage of different O. fonsencai populations by principal component analysis, which indicated that the larvae from Caatinga populations were generally smaller than the larvae from other biomes. Some of the present A. guglielmonei specimens were collected from the type locality of Antricola inexpectata. Comparisons of these specimens with the type specimens of A. inexpectata and A. guglielmonei indicated that they could not be separated by their external morphology. Hence, we are relegating A. inexpectata to a synonym of A. guglielmonei. This proposal is corroborated by our phylogenetic analysis.

Unraveling the phylogenetics of genetically closely related species, Haemaphysalis japonica and Haemaphysalis megaspinosa, using entire tick mitogenomes and microbiomes

Ticks have a profound impact on public health. Haemaphysalis is one of the most widespread genera in Asia, including Japan. The taxonomy and genetic differentiation of Haemaphysalis spp. is challenging. For instance, previous studies struggled to distinguish Haemaphysalis japonica and Haemaphysalis megaspinosa due to the dearth of nucleotide sequence polymorphisms in widely used barcoding genes. The classification of H. japonica japonica and its related sub-species Haemaphysalis japonica douglasi or Haemaphysalis jezoensis is also confused due to their high morphological similarity and a lack of molecular data that support the current classification. We used mitogenomes and microbiomes of H. japonica and H. megaspinosa to gain deeper insights into the phylogenetic relationships and genetic divergence between two species. Phylogenetic analyses of concatenated nucleotide sequences of protein-coding genes and ribosomal DNA genes distinguished H. japonica and H. megaspinosa as monophyletic clades, with further subdivision within the H. japonica clade. The 16S rRNA and NAD5 genes were valuable markers for distinguishing H. japonica and H. megaspinosa. Population genetic structure analyses indicated that genetic variation within populations accounted for a large proportion of the total variation compared to variation between populations. Microbiome analyses revealed differences in alpha and beta diversity between H. japonica and H. megaspinosa: H. japonica had the higher diversity. Coxiella sp., a likely endosymbiont, was found in both Haemaphysalis species. The abundance profiles of likely endosymbionts, pathogens, and commensals differed between H. japonica and H. megaspinosa: H. megaspinosa was more diverse.

Nuttalliellidae in Burmese amber: implications for tick evolution

Ticks are composed of 3 extant families (Argasidae, Ixodidae and Nuttalliellidae) and 2 extinct families (Deinocrotonidae and Khimairidae). The Nuttalliellidae possess one extant species (Nuttalliella namaqua) limited to the Afrotropic region. A basal relationship to the hard and soft tick families and its limited distribution suggested an origin for ticks in the Afrotropics. The Deinocrotonidae has been found in Burmese amber from Myanmar and Iberian amber from Spain, suggesting a wider distribution of the lineage composed of Deinocrotonidae and Nuttalliellidae. The current study describes 8 fossils from mid-Cretaceous (ca. 100 Ma) Burmese amber: 2 Deinocroton species (Deinocroton bicornis sp. nov.; Deinocroton lacrimus sp. nov.), 5 Nuttalliella species (Nuttalliella gratae sp. nov., Nuttalliella tuberculata sp. nov., Nuttalliella placaventrala sp. nov., Nuttalliella odyssea sp. nov., Nuttalliella tropicasylvae sp. nov.) and a new genus and species (Legionaris nov. gen., Legionaris robustus sp. nov.). The argument is advanced that Deinocroton do not warrant its own family, but forms part of the Nuttalliellidae comprising 3 genera, Deinocroton, Legionaris nov. gen. and Nuttalliella). Affinities of Burmese tick fossils to the Australasian region, specifically related to rifting of the Burma terrane from northern Australia ~150 million years ago, suggest that Nuttalliella had a much wider distribution than its current limited distribution. The distribution of Nuttalliella likely stretched from Africa over Antarctica and much of Australia, suggesting that extant members of this family may still be found in Australia. Considerations for the geographic origins of ticks conclude that an Afrotropic origin can as yet not be discarded.

Mitochondrial genome and nuclear ribosomal RNA analysis place Alveonasus lahorensis within the Argasinae and suggest that the genus Alveonasus is paraphyletic

Two major families exist in ticks, the Argasidae and Ixodidae. The Argasidae comprise 2 sub-families, Argasinae and Ornithodorinae. The placement into subfamilies illuminate differences in morphological and molecular systematics and is important since it provides insight into evolutionary divergence within this family. It also identifies fundamental gaps in our understanding of argasid evolution that provide directions for future research. Molecular systematics based on mitochondrial genomics and 18S/28S ribosomal RNA confirmed the placement of various genera and subgenera into the Argasinae: Argas (including Argas and Persicargas), Navis, Ogadenus, Otobius lagophilus, Proknekalia, Secretargas and the Ornithodorinae: Alectorobius, Antricola (including Antricola and Parantricola), Carios, Chiropterargas, Nothoaspis, Ornithodoros (including Microargas, Ornamentum, Ornithodoros sensu strictu, Pavlovskyella), Otobius sensu strictu, Reticulinasus and Subparmatus. The position of Alveonasus remains controversial since traditional taxonomy placed it in the Ornithodorinae, while cladistic and limited molecular analysis placed it in the Argasinae. The current study aimed to resolve the systematic position of Alveonasus using mitochondrial genomic and 18S/28S ribosomal RNA systematics by sequencing the type species Alveonasus lahorensis from Pakistan. In addition, the mitochondrial genomes for Argas reflexus and Alectorobius kelleyi are reported from Germany and the USA, respectively. The systematic data unambiguously place Alveonasus in the Argasinae and also suggest that Alveonasus may be another paraphyletic genus.

The complete mitogenome of Argas vulgaris (Filippova, 1961) and its phylogenetic status in subgenus Argas (Acari: Argasidae)

Soft ticks (Ixodida: Argasidae) are ectoparasites of terrestrial vertebrates with worldwide distributions. As one representative group of Argasidae, the genus Argas has an important vectorial role in transmitting zoonotic diseases. However, our knowledge of the subgenus Argas in China is still limited, as most literature only lists occurrence records or describes specific case reports without providing detailed morphological characteristics and further molecular data. This study aims to characterize Argas vulgaris through complete mitochondrial sequencing and morphological diagnostic techniques based on a batch of adult specimens collected from Ningxia Hui Autonomous Regions (NXHAR), North China. The morphology and microstructures of Ar. vulgaris and other lectotypes of argasid ticks in the subgenus Argas were also observed using a stereomicroscope. Following DNA extraction and sequencing, a complete mitochondrial sequence of Ar. vulgaris was assembled and analyzed within a phylogenetic context. The 14,479 bp mitogenome of Ar. vulgaris consists of 37 genes, including 13 genes for protein coding, two for ribosomal RNA, 22 for transfer RNA, and one for control region (D-loops). Phylogenetic analysis of Ar. vulgaris showed 98.27%-100% nucleotide identity with Ar. japonicus, indicating a close relationship between the two tick species. The morphological diagnostic features to differentiate Ar. vulgaris from other ticks within the subgenus Argas included the location of the anus and setae on the anterior lip of the female genital aperture. This study provided high-resolution scanning electron microscope images of female Ar. vulgaris and corresponding molecular data, representing valuable resources for future accurate species identification.

First record of Alectorobius coniceps (Ixodoidea: Argasidae) and Dermacentor sp. (Ixodoidea: Ixodidae) in Pakistan

Alectorobius species are soft ticks primarily infesting birds, such as swallows, while Dermacentor species are hard ticks mainly infesting mammals, such as small ruminants. This study for the first time reported on the morphological and molecular bases of two tick species, namely A. coniceps and a Dermacentor sp. in Pakistan. The former species was examined in swallows' nests in Khyber Pakhtunkhwa province, while the latter species was examined in small ruminants in Balochistan province. In total, 25 ticks were collected, with 14 ticks morphologically identified as A. coniceps (males = 9 and females = 5) and 11 ticks identified as Dermacentor sp. (males = 7 and females = 4). Following morphological identification, molecular identification was gained by obtaining 16S rDNA and cox1 sequences for these ticks. The BLAST results for the 16S rDNA and cox1 sequences from A. coniceps shared a maximum identity of 97.46% and 96.49% with the same species from Malta. The BLAST analysis of the 16S rDNA and cox1 sequences from Dermacentor sp. showed maximum identities of 98.42% and 97.45% with Dermacentor pavlovskyi from China. The phylogenetic analysis based on 16S rDNA and cox1 of A. coniceps showed a close evolutionary relationship with the same species. The case of Dermacentor sp., based on 16S DNA and cox1, indicated a close evolutionary relationship with Dermacentor pavlovskyi from China.

Argas persicus and Carios vespertilionis Ticks Infesting Ducks, Domestic Fowls and Bats in Pakistan: First Report on Molecular Survey and Phylogenetic Position of Borrelia anserina

Argasid ticks have the vectorial potential for transmitting disease-causing pathogens to avian hosts, resulting in economic losses that may not be fully estimated. Borrelia species are the responsible agents of borreliosis in poultry, animals and humans. Our previous studies have reported a high prevalence of Argas persicus infesting domestic fowls in Khyber Pakhtunkhwa (KP), Pakistan. However, molecular screening and genetic characterization of Borrelia spp. in A. persicus have been neglected in Pakistan. In this study, we focused on the molecular epidemiology and genetic characterization of Borrelia spp. associated with A. persicus ticks infesting domestic fowls and ducks, and Carios vespertilionis infesting bats in selected districts of KP. Overall, 1818 ticks, including females (415; 23%), males (345; 19%), nymphs (475; 26%) and larvae (583; 32%), were collected from 27 locations in nine districts (Peshawar, Mardan, Swabi, Charsadda, Chitral, Lakki Marwat, Bannu, Bajaur and Hangu) from domestic fowls, ducks and their shelters, and bats. A subset of 197 ticks was selected for DNA extraction and PCR to amplify fragments of the cytochrome c oxidase (cox) gene for ticks and flagellin B (flaB) for the detection and genetic characterization of associated Borrelia spp. Among these, only Borrelia anserina DNA was detected in 40 ticks (27.2%) of different life stages, where highest prevalence was found in female ticks (18; 45%), followed by nymphs (12; 30%), larvae (7; 17.5%) and males (3; 7.5%). Tick infestation in shelters (1081; 77%) was higher than on hosts (323; 23%). The resultant cox amplicons of A. persicus showed 100% identity with the same species reported from Pakistan, China, Iran, Kenya, Kazakhstan, Algeria and Egypt and C. vespertilionis show 100% identity with the species reported from Pakistan, China, Japan, Kenya, Vietnam, Spain, Netherlands, the United Kingdom and Hungry, and clustered with the aforementioned species in the phylogenetic tree. The obtained Borrelia sequences showed 100% identity with B. anserina and revealed a close resemblance to the relapsing fever group and clustered in a monophyletic clade with B. anserina from India, Iran and Brazil in a phylogenetic tree. These results establish the first molecular characterization of B. anserina in A. persicus infesting domestic fowls and ducks in the region, as well as their shelters. To effectively control zoonotic consequences, country-wide surveillance research should be encouraged to screen soft ticks infesting various birds for associated pathogens.

Description of a new Pavlovskyella species (Acari: Argasidae) from Chile

Soft ticks (Argasidae) of the Pavlovskyella Pospelova-Shtrom subgenus are important vectors of relapsing fever spirochetes, which are agents of disease globally. South American representatives of the Pavlovskyella subgenus include 3 species: Ornithodoros (Pavlovskyella) brasiliensis Aragão, Ornithodoros (Pavlovskyella) furcosus Neumann, and Ornithodoros (Pavlovskyella) rostratus Aragão. Here, we describe a fourth species based on morphological and mitogenomic evidence of ticks collected in burrows of unknown hosts in central Chile. The larva of the new species separates from other South American soft ticks by the following combination of characters: 13 pairs of dorsolateral setae, dorsal plate hexagonal, hypostome blunt with denticles from apex almost to the base. Adults of this new species lack cheeks, possess a dorsoventral groove, and have humps, similar to O. (P.) brasiliensis; however, they lack bulging structures on the flanks of idiosoma. Moreover, females and males differ from O. (P.) rostratus by having 3 humps instead of spurs in tarsi I and from O. (P.) furcosus because of their smaller size and thinner anterior lip of the genital aperture in females. The phylogenetic analysis performed with mitogenomes of the Argasidae family depicts the new Pavlovskyella species from Chile in a monophyletic clade with other South American species in the subgenus, confirming a regional group.

Distribution of the soft tick Carios vespertilionis in lowlands and low mountain regions of Germany

In Germany, the knowledge about ticks infesting bats is limited, and is restricted only to a few studies, most of them dating back decades. To further improve our knowledge on ticks parasitising bats, healthy and sick bats in central Germany were examined for ticks. In total 519 larvae and one nymph of Carios vespertilionis were collected from nine bat species: Eptesicus nilssonii, Eptesicus serotinus, Myotis daubentonii, Myotis myotis, Nyctalus leisleri, Pipistrellus nathusii, Pipistrellus pygmaeus, Pipistrellus pipistrellus, and Vespertilio murinus. Either the presence of C. vespertilionis was new for some areas or it was confirmed in some federal states in central Germany. The infestation rate was mostly low (n = 1-5 larvae/bat). However, in two cases a high number of ticks was observed. The highest infestation of 97 C. vespertilionis larvae was recorded on one Parti-coloured bat (V. murinus).

Paradigms in tick evolution

The study of tick evolution may be classified into disciplines such as taxonomy and systematics, biogeography, evolution and development (evo-devo), ecology, and hematophagy. These disciplines overlap and impact each other to various extents. Advances in one field may lead to paradigm shifts in our understanding of tick evolution not apparent to other fields. The current study considers paradigm shifts that occurred, are in the process, or may occur in future for the disciplines that study tick evolution. Some disciplines have undergone significant changes, while others may still be developing their own paradigms. Integration of these various disciplines is essential to come to a holistic view of tick evolution; however, maturation of paradigms may be necessary before this vision can be attained.

Tick (Acari: Ixodoidea) fauna and zoogeographic division of Jiangxi Province, China

Tick fauna and zoogeographic distribution of Jiangxi Province remain largely unknown due to the lack of data on distribution, occurrence, and host associations of ticks. Considering this, we collected 1,817 individual samples from natural hosts, humans, and vegetation in 18 counties/districts throughout Jiangxi Province, China, from 2015 to 2021. These 1,817 individuals were found to 13 tick species, 4 genera, and 1 family. In addition, the tick sample data from 8 sampling localities (counties and districts) reported in previous studies were also included in our data. A total of 4,021 individuals, including our sample collection and the previously reported data, were assigned to at least 18 species, 6 genera, and 2 families. One newly recorded species Dermacentor sp. (near D. steini Schulze) was found; three misidentified species (Ixodes acuminatus, Haemaphysalis spinigera, and Haemaphysalis verticalis) reported previously were deleted; and one misidentified species Dermacentor auratus Supino was revised as Dermacentor steini Schulze. In addition, we divided the tick fauna in Jiangxi Province into 5 zoogeographic areas and assigned the 18 tick species collected from 26 localities to these 5 zoogeographic areas. To summarize, our findings provide valuable information on the distribution, tick-host associations, and zoogeographic division of ticks in Jiangxi Province, China. Their molecular characterizations, phylogenetic relationships, and tick-borne pathogens that they may transmit should be further explored.

Seventy-eight entire mitochondrial genomes and nuclear rRNA genes provide insight into the phylogeny of the hard ticks, particularly the Haemaphysalis species, Africaniella transversale and Robertsicus elaphensis

Hoogstraal and Kim (1985) proposed from morphology, three groups of Haemaphysalis subgenera: (i) the "structurally advanced"; (ii) the "structurally intermediate"; and (iii) the "structurally primitive" subgenera. Nuclear gene phylogenies, however, did not indicate monophyly of these morphological groups but alas, only two mitochondrial (mt) genomes from the "structurally intermediate" subgenera had been sequenced. The phylogeny of Haemaphysalis has not yet been resolved. We aimed to resolve the phylogeny of the genus Haemaphysalis, with respect to the subgenus Alloceraea. We presented 15 newly sequenced and annotated mt genomes from 15 species of ticks, five species of which have not been sequenced before, and four new 18S rRNA and 28S rRNA nuclear gene sequences. Our datasets were constructed from 10 mt protein-coding genes, cox1, and the 18S and 28S nuclear rRNA genes. We found a 132-bp insertion between tRNA-Glu (E) gene and the nad1 gene in the mt genome of Haemaphysalis (Alloceraea) inermis that resembles insertions in H. (Alloceraea) kitaokai and Rhipicephalus (Boophilus) geigyi. Our mt phylogenies had the three species of Amblyomma (Aponomma) we sequenced embedded in the main clade of Amblyomma: Am. (Aponomma) fimbriatum, Am. (Aponomma) gervaisi and Am. (Aponomma) latum. This is further support for the hypothesis that the evolution of eyes appears to have occurred in the most-recent-common-ancestor of Amblyocephalus (i.e. Amblyomminae plus Rhipicephalinae) and that eyes were subsequently lost in the most-recent-common-ancestor of the subgenus Am. (Aponomma). Either Africaniella transversale or Robertsicus elaphensis, or perhaps Af. transversale plus Ro. elaphensis, appear to be the sister-group to the rest of the metastriate Ixodida. Our cox1 phylogenies did not indicate monophyly of the "structurally primitive", "structurally intermediate" nor the "structurally advanced" groups of Haemaphysalis subgenera. Indeed, the subgenus Alloceraea may be the only monophyletic subgenus of the genus Haemaphysalis sequenced thus far. All of our mt genome and cox1 phylogenies had the subgenus Alloceraea in a clade that was separate from the rest of the Haemaphysalis ticks. If Alloceraea is indeed the sister to the rest of the Haemaphysalis subgenera this would resonate with the argument of Hoogstraal and Kim (1985), that Alloceraea was a subgenus of "primitive" Haemaphysalis. Alectorobius capensis from Japan had a higher genetic-identity to A. sawaii, which was also from Japan, than to the A. capensis from South Africa. This indicates that A. capensis from Japan may be a cryptic species with respect to the A. capensis from South Africa.

Hard ticks in Burmese amber with Australasian affinities

Three examples of metastriate hard ticks (Ixodida: Ixodidae) with apparent affinities to modern Australasian genera are described from the mid-Cretaceous (ca. 100 Ma) Burmese amber of Myanmar. Two nymphs of Bothriocroton muelleri sp. nov. represent the oldest (and only) fossil record of this genus, living members of which are restricted to Australia and predominantly feed on monitor lizards, snakes and echidnas. A female of Archaeocroton kaufmani sp. nov. shares its basis capitulum shape with the tuatara tick Archaeocroton sphenodonti (Dumbleton, 1943), the only extant member of this genus and an endemic species for New Zealand. The presence of 2 Australasian genera in Burmese amber is consistent with a previous record of an Ixodes Latreille, 1795 tick from this deposit which resembles Australian members of this genus. They further support an emerging hypothesis that fauna of the amber forest, which may have been on an island at the time of deposition, was at least partly Gondwanan in origin. A revised evolutionary tree for Ixodida is presented compiling data from several new Burmese amber ticks described in the last few years.

Molecular characterization and phylogenetic analysis of Argas persicus (Oken, 1818) (Acari: Argasidae) from domestic birds in eastern Algeria

Argas persicus (the fowl tick) is a species of soft tick commonly associated with poultry farms. It has a wide geographic distribution and colonizes different climate regions. Morphological identification of A. persicus has been reported worldwide, but genetic data regarding its molecular characterization is limited. The present study provides data for morphological identification and genetic characterization of A. persicus collected from domestic birds in traditional farms from east Algeria (Setif region). Additionally, A. persicus samples originating from Gansu province in China were included for comparative molecular study. In total, 1518 ticks collected from 30 infested farms were examined and morphologically identified as A. persicus. Furthermore, the 14 tick samples obtained from China were morphologically identified as A. persicus. Molecular analysis of 30 ticks from Algeria (one tick from each infested farm) and the 14 Chinese samples based on PCR, sequencing, and phylogenetic analysis of three mitochondrial genetic markers (16S rRNA, 12S rRNA, and cox1) confirmed morphological results where all samples belonged to the A. persicus group. However, phylogenetic analysis showed that all Algerian samples and two Chinese samples belong to A. persicus sensu stricto (s.s.), while the remaining Chinese samples represented A. persicus sensu lato (s.l.) (divergent lineage). The present study confirms the occurrence of A. persicus s.s. both in Algeria and China, as well as provides novel molecular data for a distinct Chinese lineage of A. persicus.

Amplification and sequencing of entire tick mitochondrial genomes for a phylogenomic analysis

The mitochondrial genome (mitogenome) has proven to be important for the taxonomy, systematics, and population genetics of ticks. However, current methods to generate mitogenomes can be cost-prohibitive at scale. To address this issue, we developed a cost-effective approach to amplify and sequence the whole mitogenome of individual tick specimens. Using two different primer sites, this approach generated two full-length mitogenome amplicons that were sequenced using the Oxford Nanopore Technologies' Mk1B sequencer. We used this approach to generate 85 individual tick mitogenomes from samples comprised of the three tick families, 11 genera, and 57 species. Twenty-six of these species did not have a complete mitogenome available on GenBank prior to this work. We benchmarked the accuracy of this approach using a subset of samples that had been previously sequenced by low-coverage Illumina genome skimming. We found our assemblies were comparable or exceeded the Illumina method, achieving a median sequence concordance of 99.98%. We further analyzed our mitogenome dataset in a mitophylogenomic analysis in the context of all three tick families. We were able to sequence 72 samples in one run and achieved a cost/sample of ~ $10 USD. This cost-effective strategy is applicable for sample identification, taxonomy, systematics, and population genetics for not only ticks but likely other metazoans; thus, making mitogenome sequencing equitable for the wider scientific community.

Ticks in the metropolitan area of Berlin, Germany

A high-resolution city map showing the geographic distribution of 12 tick species (Acari: Argasidae, Ixodidae) that have been recorded from the metropolitan area of Berlin, Germany is presented. A total of 237 tick locations was mapped. These include ten ixodid tick species: Dermacentor reticulatus, Haemaphysalis concinna, Hyalomma rufipes, Ixodes ricinus, Ixodes canisuga, Ixodes hexagonus, Ixodes arboricola, Ixodes frontalis, Ixodes trianguliceps and Rhipicephalus sanguineus sensu lato. The two tick species Hy. rufipes and R. sanguineus s.l. are not endemic to Berlin. Hyalomma rufipes ticks are introduced in Europe with migratory birds from Africa every spring. Rhipicephalus sanguineus s.l. are introduced to Central Europe with dogs that had travelled to or were imported from countries where this tick is endemic. In Germany, they are able to develop and reproduce inside heated buildings. Occurrences of two soft tick species, the pigeon tick Argas reflexus and the short-legged bat tick Carios vespertilionis were also mapped. Other tick species that are likely to be endemic to Berlin and its environs, but for which documented findings or geographical coordinates are lacking, are mentioned. These include the long-legged bat tick I. vespertilionis and the marten tick I. rugicollis documented in Brandenburg, the federal state surrounding Berlin. It can be assumed that if appropriate field studies are carried out, these tick species will also be found in the metropolitan area of Berlin. The high-resolution mapping of all tick species found in a city (like Berlin) forms the basis for further investigations into the impact of climate change and changing land use on ticks and tick-borne diseases, precisely in those habitats where most people will live in the future.

A review of argasid ticks and associated pathogens of China

It has been recorded 221 species of soft ticks in the world. However, the classification system of Argasidae is still unclear with nearly two-third controversial species in genus level. Therefore, comprehensive research is still necessary. In 2016, Wen and Chen overviewed the valid species of soft ticks in China for the first time. Up to now, the soft tick fauna of China remains poorly known. Although several studies have been undertaken, the information regarding soft ticks and associated diseases are fragmentary. To facilitate the future study of this group, the scattered information on soft ticks of China is herein synthesized. Toward the end of 2021, 15 valid species of argasid ticks have been reported, of these, 9 species (60%) including Argas beijingensis, A. japonicus, A. persicus, A. sinensis, A. vespertilionis, A. vulgaris, Ornithodoros lahorensis, O. tartakovskyi, and O. papillipes have been recorded biting humans. Argas persicus is the most common species, and its borne pathogens are widely investigated, while most other argasid ticks are not sufficiently studied in China. Here, we summarize detailed information regarding hosts, geographical distribution, molecular data, and vector roles of argasid ticks in China.

Ornithodoros (Pavlovskyella) ticks associated with a Rickettsia sp. in Pakistan

Background

Soft ticks (Ixodida: Argasidae) are medically important ectoparasites that mainly feed on birds and mammals, which play a key role in their geographic distribution and dispersion. Despite their importance, studies on soft ticks are scarce for many regions and countries of the world, including Pakistan.

Methods

In this study, 2330 soft ticks—179 larvae (7.7%), 850 nymphs (36.4%), 711 males (30.5%) and 590 females (25.3%)—were collected from animal shelters in 18 locations within five districts of Khyber Pakhtunkhwa, Pakistan. A subset of the collected ticks was processed for DNA extraction and polymerase chain reaction (PCR) for the amplification of tick 12S ribosomal DNA (rDNA), 16S rDNA and cytochrome c oxidase subunit I (cox1), and rickettsial 16S rDNA gene fragments. The obtained sequences were used for the construction of a phylogenetic tree.

Results

All the specimens were morphologically identified as Ornithodoros, and were morphologically similar to Ornithodoros tholozani. The genus was confirmed by sequencing partial 12S rDNA, 16S rDNA and cox1 gene fragments. Additionally, a Rickettsia sp. was detected in some of the collected ticks by PCR targeting 16S rDNA. The morphological relatedness of the tick specimens with O. tholozani was confirmed by phylogenetic analysis, in which the Ornithodoros sp. clustered with Ornithodoros tholozani and Ornithodoros verrucosus, both of which belong to the subgenus Pavlovskyella and have been previously reported from Israel, Ukraine and Iran. The phylogenetic tree also indicated that the Ornithodoros sp. from Pakistan corresponds to an undetermined species. Furthermore, the associated Rickettsia sp. grouped with the limoniae group of Rickettsia species previously reported from Argas japonicus ticks from China.

Conclusions

This is the first molecular study of an Ornithodoros species from Pakistan. Further studies are essential to confirm its identity and possible pathogenicity with regard to its associated microorganisms in the studied region.

Graphical abstract

Description of the female, nymph and larva and mitochondrial genome, and redescription of the male of Ixodes barkeri Barker, 2019 (Acari: Ixodidae), from the short-beaked echidna, Tachyglossus aculeatus, with a consideration of the most suitable subgenus for this tick

Background

Ixodes barkeri, a tick with a distinctive ventrolateral horn-like projection on palpal segment 1, was described in 2019 from two male ticks from the Wet Tropics of Far North Queensland, Australia. However, females lie at the core of the taxonomy and subgenus classification of Ixodes; hence, we sought specimens of female ticks, successfully recovering females, plus nymphs and larvae. Mitochondrial genomes are also desirable additions to the descriptions of species of ticks particularly regarding subgenus systematics. So, we sequenced the mt genomes of I. barkeri Barker, 2019, and the possible relatives of I. barkeri that were available to us (I. australiensis Neumann, 1904, I. fecialis Warburton & Nuttall, 1909, and I. woyliei Ash et al. 2017) with a view to discovering which if any of the subgenera of Ixodes would be most suitable for I. barkeri Barker, 2019.

Results

The female, nymph, larva and mitochondrial genome of Ixodes barkeri Barker, 2019, are described for the first time and the male of I. barkeri is redescribed in greater detail than previously. So far, I. barkeri is known only from a monotreme, the short-beaked echidna, Tachyglossus aculeatus (Shaw, 1792), from the highland rainforests of the Wet Tropics of Far North Queensland, Australia.

Conclusions

Our phylogeny from entire mitochondrial genomes indicated that I. barkeri and indeed I. woyliei Ash et al., 2017, another tick that was described recently, are best placed in the subgenus Endopalpiger Schulze, 1935.

Graphical Abstract

Novel symbionts and potential human pathogens excavated from argasid tick microbiomes that are shaped by dual or single symbiosis

Research on vector-associated microbiomes has been expanding due to increasing emergence of vector-borne pathogens and awareness of the importance of symbionts in the vector physiology. However, little is known about microbiomes of argasid (or soft-bodied) ticks due to limited access to specimens. We collected four argasid species (Argas japonicus, Carios vespertilionis, Ornithodoros capensis, and Ornithodoros sawaii) from the nests or burrows of their vertebrate hosts. One laboratory-reared argasid species (Ornithodoros moubata) was also included. Attempts were then made to isolate and characterize potential symbionts/pathogens using arthropod cell lines. Microbial community structure was distinct for each tick species. Coxiella was detected as the predominant symbiont in four tick species where dual symbiosis between Coxiella and Rickettsia or Coxiella and Francisella was observed in C. vespertilionis and O. moubata, respectively. Of note, A. japonicus lacked Coxiella and instead had Occidentia massiliensis and Thiotrichales as alternative symbionts. Our study found strong correlation between tick species and life stage. We successfully isolated Oc. massiliensis and characterized potential pathogens of genera Ehrlichia and Borrelia. The results suggest that there is no consistent trend of microbiomes in relation to tick life stage that fit all tick species and that the final interpretation should be related to the balance between environmental bacterial exposure and endosymbiont ecology. Nevertheless, our findings provide insights on the ecology of tick microbiomes and basis for future investigations on the capacity of argasid ticks to carry novel pathogens with public health importance.

Maps of ticks (Acari: Argasidae, Ixodidae) for Austria and South Tyrol, Italy

A first compilation of georeferenced tick locations in Austria and South Tyrol, Italy, is presented here. This allows the tick fauna to be examined in the various climatic regions of the European Alps. The dataset comprises 424 tick locations of Austria and 48 tick locations of South Tyrol, which were digitized from literature and visualized in the form of geographical maps. The tick fauna of Austria includes two species of Argasidae in the genera Argas and Carios and 15 species of Ixodidae in the genera Dermacentor, Haemaphysalis, and Ixodes, altogether 17 tick species. In addition, two species of Ixodidae in the genera Hyalomma (each spring imported by migratory birds) and Rhipicephalus (occasionally imported by dogs returning from abroad with their owners) are included in the tick atlas. Of these, the georeferenced locations of 18 tick species are depicted in maps. The occurrence of the one remaining tick species, Ixodes inopinatus, is given at the level of the federal states. The first Austrian distribution map of the long-legged bat tick Ixodes vespertilionis, which was reported from 21 caves, deserves special mention. The most common and widespread tick species is Ixodes ricinus, with records in all nine federal states of Austria, followed by Ixodes canisuga, Ixodes hexagonus, and I. vespertilionis in six federal states each. Haemaphysalis concinna and Dermacentor reticulatus are only endemic in the eastern plains, while Dermacentor marginatus only occurs in the west, in the Tyrolean Alpine valleys. Eight tick species were reported from South Tyrol, Italy. There, the most frequently flagged tick from the vegetation is also I. ricinus, while D. marginatus and Haemaphysalis punctata are often collected from sheep. The locations are shown together with those from North and East Tyrol on a separate Tyrol map. The tick atlas in Austria and South Tyrol as well as the underlying digital dataset in the supplement contribute to the closing of data gaps in global distribution maps of ticks and improve the data basis for new species distribution models.

Rhipicephalus Capensis (Acari: Ixodidae), A geographically restricted South African tick, returning with a human traveler to the United States

Accelerated frequency of recreational travel, globalization of business, and legal and illegal plant and animal trades have contributed to enduring introductions of exotic ticks into the United States. We herein report a new incursion of a female Rhipicephalus capensis on a human traveler returning to Connecticut from South Africa. Natural distribution of R. capensis is restricted to the Western Cape Province and southwestern portion of the Northern Cape Province of South Africa, an area called the Fynbos Biome, and adults of this species primarily parasitize large, wild ungulate hosts. Only one previous international introduction of this tick is documented on imported South African plant material into the United States in 1985. The specimen described here was identified initially by morphological means and subsequently, a partial DNA sequence for the mitochondrial ribosomal RNA gene was generated in a PCR assay, which showed 94.86% identity to an R. capensis sequence in GenBank. We also provide information on several other previously unreported or under-reported incursions by South African ticks into the United States in association with imported Fynbos floricultural materials and speckled Cape tortoises, Chersobius signatus. Documentation of these additional exotic tick species incursions highlights ongoing challenges of the international movement of humans, animals, and other goods carrying ticks of human and veterinary importance.

Redescription and molecular characterization of the tick Argas japonicus Yamaguti, Clifford & Tipton, 1968 (Ixodida: Argasidae)

Species of the genus Argas are parasites that transmit pathogens, eubacteria, and viruses. Argas japonicus Yamaguti, Clifford & Tipton, 1968 was described based on specimens collected from Japan and Korea. Recently, A. japonicus was reported in different areas of China, suggesting that it may be widely distributed. Here, we have redescribed the female, male, and nymphal stages of A. japonicus and provided scanning electron microscope images based on specimens collected in Neimenggu, China. In addition, we compared four A. japonicus individuals with Argas 16S rDNA and cytochrome c oxidase subunit 1 sequences obtained from GenBank.

Reconstruction of mitochondrial genomes from raw sequencing data provides insights on the phylogeny of Ixodes ticks and cautions for species misidentification

High-throughput sequencing (HTS) technology has profoundly been involved in sequencing whole genomes of several organisms in a fast and cost-effective manner. Although HTS provides an alternative biomonitoring method to the time-consuming and taxonomy-expertise dependent morphological approach, still we cannot rule out the possibility of the impediment and misidentification biases. In this article we aim to retrieve whole mitochondrial genome (mitogenome) sequences from publicly available raw sequencing data for phylogenetic comparison of Ixodes persulcatus. For this comparison, we sequenced whole mitogenomes of four I. persulcatus ticks from Japan and constructed mitogenomes from raw sequencing data of 74 I. persulcatus ticks from China. Bayesian phylogenetic trees were inferred by the concatenated fifteen mitochondrial genes. We further tested our results by the phylogenetic analysis of cytochrome c oxidase subunit 1 (cox1) gene and internal transcribed spacer 2 (ITS2) sequences. Our findings showed that 70 constructed mitogenomes from China were clustered with the sequenced four mitogenomes of I. persulcatus from Japan. We also revealed that mitogenome sequences retrieved from two data sets CRR142297 and CRR142298 were clustered with Ixodes nipponensis. Moreover, other two mitogenome sequences from CRR142310 and CRR142311 formed a clade with Ixodes pavlovskyi. The phylogenetic analysis of cox1 gene and ITS2 sequences confirmed the identification errors of these four samples. The overall phylogenetics in our study concluded that accurate morphological identification is necessary before implementing HTS to avoid any misidentification biases.

Transcriptomic Analysis of Salivary Glands of Ornithodoros brasiliensis Aragão, 1923, the Agent of a Neotropical Tick-Toxicosis Syndrome in Humans

Tick salivary glands produce and secrete a variety of compounds that modulate host responses and ensure a successful blood meal. Despite great progress made in the identification of ticks salivary compounds in recent years, there is still a paucity of information concerning salivary molecules of Neotropical argasid ticks. Among this group of ticks, considering the number of human cases of parasitism, including severe syndromes and hospitalization, Ornithodoros brasiliensis can be considered one of the major Neotropical argasid species with impact in public health. Here, we describe the transcriptome analysis of O. brasiliensis salivary glands (ObSG). The transcriptome yielded ~14,957 putative contigs. A total of 368 contigs were attributed to secreted proteins (SP), which represent approximately 2.5% of transcripts but ~53% expression coverage transcripts per million. Lipocalins are the major protein family among the most expressed SP, accounting for ~16% of the secretory transcripts and 51% of secretory protein abundance. The most expressed transcript is an ortholog of TSGP4 (tick salivary gland protein 4), a lipocalin first identified in Ornithodoros kalahariensis that functions as a leukotriene C₄ scavenger. A total of 55 lipocalin transcripts were identified in ObSG. Other transcripts potentially involved in tick-host interaction included as: basic/acid tail secretory proteins (second most abundant expressed group), serine protease inhibitors (including Kunitz inhibitors), 5' nucleotidases (tick apyrases), phospholipase A₂, 7 disulfide bond domain, cystatins, and tick antimicrobial peptides. Another abundant group of proteins in ObSG is metalloproteases. Analysis of these major protein groups suggests that several duplication events after speciation were responsible for the abundance of redundant compounds in tick salivary glands. A full mitochondrial genome could be assembled from the transcriptome data and confirmed the close genetic identity of the tick strain sampled in the current study, to a tick strain previously implicated in tick toxicoses. This study provides novel information on the molecular composition of ObSG, a Brazilian endemic tick associated with several human cases of parasitism. These results could be helpful in the understanding of clinical findings observed in bitten patients, and also, could provide more information on the evolution of Neotropical argasids.

Argasid Ticks of Palearctic Bats: Distribution, Host Selection, and Zoonotic Importance

The soft ticks (Ixodida: Argasidae) are ectoparasites of terrestrial vertebrates with a wide geographic distribution, occurring on all continents. These ticks are obligate blood-feeders, most of them show high degrees of host-specialization and several species in arid and tropical regions are important parasites of livestock and men. Species commonly occurring on domestic animals and man are generally well-known, with many studies focusing on their ecology, distribution or vectorial role. However, wildlife-specialist soft ticks are less studied. Nearly half of all soft tick species are bat specialists, with five species (Carios vespertilionis, Chiropterargas boueti, Chiropterargas confusus, Reticulinasus salahi, and Secretargas transgariepinus) occurring in the Western Palearctic. There is no comprehensive study on the distribution, hosts or pathogens in these soft ticks, although most species were shown to carry several viral, bacterial, or protozoan pathogens and also to occasionally infest humans. Based on a literature survey and 1,120 distinct georeferenced records, we present here the geographical range, host selection and vectorial potential for bat-specialist soft ticks occurring in the Western Palearctic (chiefly Europe, North Africa, and the Middle East). Carios vespertilionis shows the largest distribution range and was found on most host species, being ubiquitous wherever crevice-roosting bats occur. All the other species were located only in areas with Mediterranean climate, with Ch. boueti, Chiropteraragas confusus, and R. salahi are missing entirely from Europe. These three species have a host spectrum of bats roosting primarily in caves, while S. transgariepinus and Ca. vespertilionis is feeding primarily on crevice-roosting bat species. All but one of these soft tick species are known to feed on humans and may be vectors of important disease agents (Rickettsia spp., Borrelia spp., Bartonella spp., Ehrlichia spp., Babesia spp., several nairo-, and flaviviruses). As several crevice-roosting bat species show a continuous adaptation to human-altered areas, with certain species becoming common city-dwellers in the Western Palearctic, the study of bat specialist soft ticks is also important from an epidemiologic point of view.

Pitfalls in Tick and Tick-Borne Pathogens Research, Some Recommendations and a Call for Data Sharing

An understanding of the relationships of ticks and tick-borne pathogens can only be achieved by integrating data from multiple studies. The publication of raw material is a necessary step for wide-area meta-analyses and study design, data collection and reporting require harmonization. This is an opinion paper, not a consensus position, and is open to debate. This work reflects our view about how data should be communicated in mainstream journals. We indicate rules that should be observed in recording weather data, to avoid serendipitous correlations between the density of ticks and climate variables and recommend the inclusion of raw data in reports. We stress the need for standardized methods to collect ticks that cannot be obtained by standard flagging. The reporting of infection rates of pathogens in ticks should avoid conclusions based on pure molecular findings in feeding ticks. Studies demonstrating the vectorial capacity of ticks should not be supported only by molecular surveys of feeding ticks. Vacuous conclusions about vectorial or reservoir status based solely on the finding of genomic material of a pathogen should be discouraged. We stress that phylogenetic studies based on random selection of sequences from GenBank are unsuitable. We firmly support the development of a dedicated server of curated sequences of ticks and pathogens as a standard for future studies.

First Record of a Suspected Human-Pathogenic Borrelia Species in Populations of the Bat Tick Carios vespertilionis in Sweden

The bat tick Cariosvespertilionis has been reported from Sweden to occasionally feed on humans resulting in disease symptoms. The aim of this study was to investigate C. vespertilionis as a potential vector and reservoir of Borrelia species. In 2015 and 2018 in south-central Sweden, C. vespertilionis ticks were collected from a wooden bat box harboring Soprano pipistrelle bats, Pipistrellus pygmaeus. In addition, one C. vespertilionis tick found inside a house in southern Sweden in 2019 was collected. Ticks were screened for Borrelia spp. using a genus-specific quantitative PCR assay. The Borrelia species of the positive specimens were determined by conventional PCR followed by DNA sequencing and phylogenetic analyses. A total of 24% (22 of 92) of the analyzed C. vespertilionis ticks were Borrelia-positive. Phylogenetic analyses indicate that the bacteria belong to the relapsing fever group of borreliae; some of them appear to be identical with Borrelia sp. CPB1, a spirochete only found twice before-in the United Kingdom and in France. Our results also indicate a temporal and spatial distribution of this Borrelia species. Since C. vespertilionis occasionally bites humans, and since it exhibits a high prevalence of Borrelia bacteria, it is possible that it presents a risk of human disease. Further studies are needed to characterize Borrelia sp. CPB1 to determine if it is human-pathogenic and to determine if C. vespertilionis is a vector and/or reservoir of this agent.

A new species of soft tick from dry tropical forests of Brazilian Caatinga

Ornithodoros tabajara n. sp. is described from laboratory-reared larvae and adult specimens collected in the Brazilian Caatinga. This new species shares the ecological niche with Ornithodoros rietcorreai and is likely associated with colonial rodents of genus Kerodon. However, O. tabajara n. sp. is morphologically easy to distinguish from O. rietcorreai and other Neotropical Ornithodoros by a unique combination of characters: larva with 17 pairs of dorsal setae (seven anterolateral, three central and seven posterolateral), sub-oval dorsal plate, hypostome blunt apically with dentition formula 2/2 along its extension, only one pair of posthypostomal setae, six pairs of sternal setae, posteromedian setae absent, and leave-shaped anal valves; alive adults with whitish islands of mammillae symmetrically distributed on dorsum (not visible in ethanol-preserved specimens), and median disk merging with posteromedian file. A phylogenetic analysis performed with mitochondrial 16S rDNA sequences points O. tabajara n. sp. as O. rietcorreai's sister taxon, which rises the hypothesis of sympatric speciation.

Atlas of ticks (Acari: Argasidae, Ixodidae) in Germany

An updated and increased compilation of georeferenced tick locations in Germany is presented here. This data collection extends the dataset published some years ago by another 1448 new tick locations, 900 locations of which were digitized from literature and 548 locations are published here for the first time. This means that a total of 3492 georeferenced tick locations is now available for Germany. The tick fauna of Germany includes two species of Argasidae in the genera Argas and Carios and 19 species of Ixodidae in the genera Dermacentor, Haemaphysalis, and Ixodes, altogether 21 tick species. In addition, three species of Ixodidae in the genera Hyalomma (each spring imported by migratory birds) and Rhipicephalus (occasionally imported by dogs returning from abroad with their owners) are included in the tick atlas. Of these, the georeferenced locations of 23 tick species are depicted in maps. The occurrence of the one remaining tick species, the recently described Ixodes inopinatus, is given at the level of the federal states. The most common and widespread tick species is Ixodes ricinus, with records in all 16 federal states. With the exception of Hamburg, Dermacentor reticulatus was also found in all federal states. The occurrence of the ixodid ticks Ixodes canisuga, Ixodes frontalis, Ixodes hexagonus and I. inopinatus were documented in at least 11 federal states each. The two mentioned argasid tick species were also documented in numerous federal states, the pigeon tick Argas reflexus in 11 and the bat tick Carios vespertilionis in seven federal states. The atlas of ticks in Germany and the underlying digital dataset in the supplement can be used to improve global tick maps or to study the effects of climate change and habitat alteration on the distribution of tick species.