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There is limited knowledge about tick diversity in the Amazon region. Here, we survey small terrestrial mammals for tick infestation at the Rio Pardo settlement, Amazonas State, Brazil. Sampling included rainy and dry seasons and four ecotones (primary forest, forest in regeneration, field crops and households). Each animal was inspected for ticks, which, if present, were placed in 70% alcohol and identified. Parasitological indexes were calculated and the presence/absence of ticks on hosts was tested for possible associations with independent variables (ecotone, host sex, host order, host family, host age and season). A total of 208 small mammals were captured, 47 individuals (10 species) in the primary forest, 124 (15 species) in the forest in regeneration, 11 (7 species) in the field crops, and 26 (4 species) in the households. A total of 14 small mammals were infested by ticks (overall prevalence: 6.7%; 95% CI: 3.72 - 11.04%), which consisted of 51 specimens that were identified into four species, as follows: Amblyomma humerale (32 nymphs); Ixodes luciae (6 females); Amblyomma coelebs (1 nymph); and Ornithodoros mimon (1 larva). In addition, 11 larvae were retained as Amblyomma spp. Only host order showed association (P = 0.002) with tick infestation, with marsupials 5.5 times more infested than rodents. Our record of O. mimon on D. marsupialis is the first on this host species, and the first record of a Argasidae tick in the Brazilian state of Amazonas. To the best of our knowledge, this is the first study that actively screened free-living terrestrial small mammals and provided data on prevalence, mean intensity and mean abundance of tick infestations in the Brazilian Amazonas state.

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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.

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Os carrapatos, artrópodes hematófagos, são vetores de doenças tais como febre maculosa das Montanhas Rochosas ou do Mediterrâneo, doença de Lyme, encefalite transmitida por carrapatos, babesiose e etc. No entanto, os fluidos dos carrapatos (saliva e hemolinfa) são misturas ricas em moléculas que exercem interessantes atividades farmacológicas, por exemplo, anticoagulante, antitumoral, antimicrobiana, dentre outras. Assim, os fluidos dos carrapatos podem ser considerados como potenciais fontes para a descoberta de novos medicamentos. Os carrapatos moles, denominados Argasídeos, são ectoparasitas que possuem hábitos alimentares característicos, pois excretam o excesso de sangue ingerido através de suas glândulas coxais, produzindo assim um fluido conhecido como líquido coxal (LC), mistura que contém carboidratos, proteínas, lipídios e ácidos nucléicos. O Ornithodoros rostratus é um dos argasídeos encontrados na América do Sul, principalmente no Brasil, Argentina, Paraguai e Bolívia, entretanto, até o momento, o líquido coxal de O. rostratus ainda não foi bem caracterizado. Portanto, os objetivos deste trabalho foram realizar uma caracterização bioquímica e verificar a atividade antibacteriana do LC do carrapato O. rostratus fracionado através de um protocolo otimizado. Para isto, aproximadamente 3,5 mL de LC foi coletado, esterilizado (membrana de 0,22 μm), liofilizado e reconstituído e, posteriormente, fracionado de acordo com sua massa molecular através de uma membrana de corte de 10 kDa (Amicon). Este procedimento resultou nas frações de Líquido Coxal de Alta Massa Molecular (LCAM) e Líquido Coxal de Baixa Massa Molecular (LCBM), as quais tiveram suas concentrações proteicas determinadas por BCA e por absorbância (em 214; 260 e 280 nm); além disso essas amostras foram submetidas aos ensaios bioquímicos por SDS-PAGE, RP-HPLC, análise proteômica, determinação de massas moleculares por MALDI-TOF e análise de atividade antibacteriana (inibição de crescimento de Staphylococcus aureus e Escherichia coli). Posteriormente as amostras LCAM e LCBM foram fracionadas por troca iônica utilizando membrana SDB-XC e as amostras obtidas foram analisadas por MALDI-TOF. A análise SDS-9 PAGE mostrou que as amostras LC e LCAM possuem três bandas proteicas principais (aproximadamente 60; 25 e 15 kDa) e como esperado, a amostra LCBM não apresentou bandas proteicas. A análise das amostras LCB, LCAM e LCBM por RP- HPLC resultou respectivamente em 26; 20 e 31 picos majoritários. A amostra LCBM (concentração proteica de 0,1μg/μL e sem alteração de pH) inibiu o crescimento de S. aureus, no entanto, nenhuma das amostras ensaiadas inibiram o crescimento de E. coli. A análise proteômica do LC resultou em 164 proteínas de artrópodes e 31 proteínas antimicrobianas quando comparados com seus respectivos banco de dados. Por sua vez, a análise proteômica de LCAM concentrado resultou em 500 proteínas de artrópodes e 264 proteínas antimicrobianas. Tendo em vista o elevado número de proteínas encontradas no LC, existe uma grande possibilidade de alguns desses compostos inibirem o crescimento de S. aureus.

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Introduction: Ticks are obligate hematophagous ectoparasitic arthropods of great relevance to public health, being vectors of various diseases. Ornithodoros brasiliensis (Acari: Argasidae) are endemic to the mountainous region of Rio Grande do Sul, Brazil. Their salivary composition contains bioactive molecules capable of modulating the immune system and affecting the host's hemostasis with local and systemic effects. Objectives: To characterize the anticoagulant activity of the salivary gland extract (SGE) of the tick Ornithodoros brasiliensis on blood coagulation. Methods: The EGSs were obtained by macerating the ticks' salivary glands, generating 2 different extracts (EGS-1 and EGS-2), after which the amount of protein was estimated by absorbance at 280 nm. SDS-PAGE 12.5% was used to analyze the protein profile of the samples and the biological test was carried out on the L1 and L2 larvae of the nematode Caenorhabditis elegans. EGS-1 was filtered on Amicon according to molecular weight (30, 10 and 3kDa) and the fractions obtained were subjected to RP-HPLC chromatography (C18). The chromatography samples and EGS-1 in different concentrations were tested in the rotational thromboelastometry equipment (Rotem®) (0.2 to 1.03 μg/well), as well as in the FXa and thrombin inhibition tests using chromogenic substrates (S2765 and S2238, respectively) (0.40 to 0.207 μg/test), following protocols pre- established by the laboratory and the equipment manual. EGS-2 was submitted in different concentrations (6.5 to 52 ng/well) to the rotational thromboelastometry test, and the global coagulation tests were carried out in duplicate, Prothrombin Time (PT) and Activated Thromboplastin Time (aPTT), using the commercial kits, with different concentrations of ESG-2 (6.5 to 97.5 ng/test) and finally FXa and thrombin inhibition tests using chromogenic substrates (S2765 and s2238, respectively) at a concentration of 6.5 ng/test. Results: EGS-1 showed in the protein dosage (1.118 μg/ml) and EGS-2 (6.5 μg/ml). In the activity test, the EGSs showed temporary and reversible paralysis. EGS-2 showed a prolongation of the clotting time with incoagulobility from 52 ng/well in the rotational thromboelastometry test. In TP, inhibition was 28.5% at 97.5 ng/well and in TTPa 48.6% at 78 ng/well. Thrombin inhibition averaged 13.7% and factor Xa inhibition averaged 30%. In relation to the chromatographic fractions, the P4 fraction showed a prolongation of the coagulation time in the rotational thromboelastometry test. The P3 fraction had a 25.4% inhibition of thrombin formation. The P4 fraction inhibited Factor Xa by 36.9%. Conclusion: The EGS of the O. brasiliensis tick has anticoagulant action, reaching incoagulability with 52ng/test in the rotational thromboelastometry assay and at least two proteins acting in the process. One of them is linked to thrombin, with the P3 fraction showing the greatest inhibition, and the other is linked to FXa inhibition, with the P4 fraction being more evident. The rotational thromboelastometry test showed an alteration, indicating an inhibitory action on the formation of fibrin networks.

Introdução: Os carrapatos são artrópodes ectoparasitas hematófagos obrigatórios, de grande relevância para a saúde pública, sendo vetores de diversas doenças. Os Ornithodoros brasiliensis (Acari: Argasidae) são endêmicos da região serrana do Rio Grande do Sul, Brasil. Na sua composição salivar possui a presença de moléculas bioativas capazes de modular o sistema imunológico e afetar a hemostasia do hospedeiro com efeitos locais e sistêmicos. Objetivos: Caracterizar a atividade anticoagulante do extrato da glândula salivar (EGS) do carrapato Ornithodoros brasiliensis sobre a coagulação sanguínea Métodos: Os EGS’s foram obtidos por maceração das glândulas salivares dos carrapatos, gerando 2 extratos distintos (EGS-1 e EGS-2), em seguida, a quantidade de proteínas foi estimada por absorbância a 280 nm. O SDS-PAGE 12,5% foi usado para analisar o perfil proteico das amostras e o teste biológico foi realizado nas larvas L1 e L2 do nematoide Caenorhabditis elegans. O EGS-1 foi submetido à filtração em Amicon de acordo com peso molecular (30, 10 e 3kDa) e as frações obtidas foram submetidas a cromatografia RP-HPLC (C18). As amostras da cromatografia e o EGS-1 em diferentes concentrações foram testados no equipamento de tromboelastometria rotacional (Rotem®) (0,2 a 1,03 μg/poço), como também nos testes de inibição do FXa e trombina utilizando substratos cromogênicos (S2765 e S2238, respectivamente) (0,40 a 0,207 μg/teste), seguindo protocolos pré-estabelecidos pelo laboratório e o manual dos equipamentos. O EGS-2 foi submetido em diferentes concentrações (6,5 a 52 ng/poço) ao teste de tromboelastometria rotacional, sendo realizados os testes globais de coagulação em duplicada, Tempo de Protrombina (TP) e Tempo de Tromboplastina Activada (TTPa), utilizando os kits comerciais, com diferentes concentrações de ESG-2 (6,5 a 97,5 ng/teste) e por fim submetidos testes de inibição do FXa e trombina utilizando substratos cromogênicos (S2765 e s2238, respectivamente) em uma concentração de 6,5 ng/teste. Resultados: O EGS- 1 apresentou na dosagem proteica (1,118 μg/ml) e o EGS-2 (6,5 μg/ml). No teste de atividade os EGS’s apresentaram uma paralisia temporária e reversível. O EGS-2 apresentou um prolongamento no tempo de coagulação com incoagulobilidade a partir de 52 ng/poço no teste de tromboelastometria rotacional. No TP a inibição foi de 28,5% com 97,5 ng/poço e em TTPa de 48,6% com 78 ng/poço. Na inibição de trombina, teve uma média de inibição de 13,7% e na inibição de fator Xa uma média de 30%. Em relação às frações cromatográficas, a fração P4 apresentou um prolongamento no tempo de coagulação no teste de tromboelastometria rotacional. A fração P3 obteve uma inibição de 25,4% na formação de trombina. A fração P4 obteve uma inibição de 36,9% na inibição de Fator Xa. Conclusão: O EGS do carrapato O. brasiliensis apresenta ação anticoagulante chegando a incoagulabilidade com 52ng/teste no ensaio de tromboelastometria rotacional e pelo menos duas proteínas atuantes no processo. Uma delas ligada a trombina com a representação da fração P3 com maior inibição e outra ligada a inibição do FXa sendo mais evidente com a fração P4. No teste de Tromboelastometria rotacional mostrou uma alteração, apontando uma ação inibitória na formação das redes de fibrina.

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Ticks are obligate hematophagous parasites that can transmit to vertebrate hosts several pathogens, including viruses, bacteria, protozoa and helminths. Among these agents, some Borrelia species some Borrelia species cause disease in humans and other vertebrate hosts; therefore, they have medical and veterinary health importance. To gather additional information on Borrelia species in Brazil, the current study aimed to detect the presence of these species in Ornithodoros cavernicolous ticks collected in September 2019 from cement pipes that are used by bats as shelter in a farm located in the midwestern region of Brazil. DNA samples obtained from 18 specimens of O. cavernicolous were subjected of two polymerase chain reactions, targeting a segment of the Borrelia fla B gene. Of the samples tested, only one (6 %, 1/18) showed amplification. The nucleotide sequence of the amplified DNA showed more than 97 % (293/300) identity with a sequence of a Borrelia sp. detected in blood collected from a bat from Macaregua Cave, Colombia, and more than 97 % (292/300) detected in lungs from vampire bats from northeastern Brazil. The deduced amino acid sequences were identical to each other. Phylogenetic analysis indicated that these sequences formed a group of Borrelia species (putatively associated with bats) that is closely related to sequences of Borrelia species of the Lyme borreliosis group. Further investigations should be carried out in order to determine whether the sequence of the Borrelia sp. we found belongs to a new taxon. It will also be of great importance to determine which vertebrate hosts, besides bats, O. cavernicolous ticks can parasitize in order to investigate whether the Borrelia sp. we found may be transmitted and cause disease to the other vertebrate hosts.

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Babesia spp. are tick-borne protozoans that involve birds and mammals in their transmission cycles and cause babesiosis, a severe hemolytic malaria-like disease. Opossums of the genus Didelphis are recognized hosts of tick-borne pathogens. Therefore, exploring tick-borne agents in Didelphis species is important to understand the circulation of pathogens in areas where opossums occur. In this study, we targeted Anaplasmataceae, Babesia, Borrelia and Hepatozoon DNA in ticks, blood and organ samples collected from three hunted Didelphis marsupialis specimens in eastern Guatemala. While the samples were negative for Hepatozoon and bacterial DNA, sequences of Babesia 18S rDNA, cox1 and cytb genes were retrieved from two opossums. Ticks collected on the animals included Amblyomma parvum and an undetermined Ornithodoros sp. The Babesia sp. detected in this study (Babesia sp. THB1-2) clusters phylogenetically within the "Western Babesia group", which includes pathogenic species such as Babesia conradae, Babesia duncani, and Babesia negevi. Our results represent the first record of a Babesia sp. in Guatemala and highlight the importance of D. marsupialis as potential spreaders of ticks and pathogens in Central America.

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Introduction: Ornithodoros erraticus and Ornithodoros moubata are the main vectors of African swine fever virus (ASFV) and the human relapsing fever spirochetes Borrelia hispanica and Borrelia crocidurae in the Mediterranean region and Borrelia duttoni in continental Africa. Manipulation of the tick microbiome has been shown to reduce vector fitness and competence in tick vectors, suggesting that the identification of key microbial players associated with tick tissues can inform interventions such as anti-microbiota vaccines to block pathogen development in the midgut and/or salivary glands. Methods: In this study, we analyzed and compared the microbiome of the salivary glands and midgut of O. erraticus and O. moubata. For the taxonomic and functional characterization of the tissue-specific microbiome, we used 16S rRNA amplicon sequencing and prediction of metabolic profiles using PICRUSt2. Co-occurrence networks were built to characterize the community assembly and identify keystone taxa in each tick species. Results: Our results revealed differences in the composition, diversity, and assembly of the bacterial microbiome of salivary glands and midgut within each tick species, but differences were more noticeable in O. moubata. Differences were also found in the microbiome of each tissue, salivary gland and midgut, between species. However, the 'Core Association Networks (CAN)' analysis revealed conserved patterns of interacting taxa in tissues within and between tick species. Different keystone taxa were identified in O. erraticus and O. moubata tissues, but Muribaculaceae and Alistipes were found as keystone taxa in the salivary glands of both tick species which justifies their use as anti-microbiota vaccine candidates to alter the microbiome and reduce tick fitness and/or block pathogen transmission. The high similarity of predicted metabolic pathways profiles between tissues of the two tick species suggests that taxonomic variability of the microbiome is not associated with significant changes in microbial functional profiles. Conclusion: We conclude that the taxonomic structure of the microbiome in O. erraticus and O. moubata is tissue-specific, suggesting niche partitioning of bacterial communities associated to these soft ticks. However, shared keystone taxa and conserved patterns of interacting taxa between tissues and tick species suggest the presence of key microbial players that could be used as anti-microbiota vaccine candidates to affect tick physiology and/or pathogen colonization.

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Records of accidental parasitism by ticks in humans from Brazil are scarce, with most being reported by researchers who are parasitized during their research and by professionals who work with animals. In order to compile these records, an extensive literature review was carried out. Our revision includes studies published between 1909 and 2022, including nine species of the Argasidae family and 32 species of the Ixodidae family that were reported biting humans in the six biomes of the Brazilian territory. The species with the highest number of records of human parasitism was Amblyomma sculptum, followed by Amblyomma coelebs, Amblyomma cajennense sensu stricto, and Amblyomma brasiliense. The Atlantic Forest was the most frequent biome where human parasitism occurred, probably due to the greater number of inhabitants, universities, and researchers in the region; however, this does not mean that this biome is more conducive to the development of ticks and their parasitism in humans. In addition to Amblyomma ovale, a vector of Rickettsia parkeri in the country, two of the main species that act as vectors of Rickettsia rickettsii, A. sculptum, and Amblyomma aureolatum, have been reported, which is quite worrying considering that the wide distribution of the species and life stages most frequently mentioned in parasitism (i.e., nymphs and adults) are the ones that favour pathogen transmission. This research provides a significant contribution to the knowledge of tick species associated with human parasitism in Brazil; however, due to environmental change potentiated by deforestation and fires, it is expected that there will be a geographic expansion of some tick species and the pathogens that use them as a vector and an increase in human parasitism.

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Relapsing fever group Borrelia (RFGB) are motile spirochetes transmitted to mammalian or avian hosts through the bite of hematophagous arthropods, such as soft ticks (Argasidae), hard ticks (Ixodidae) and the human clothing lice. RFGB can infect pets such as dogs and cats, as well as birds, cattle and humans. Borrelia recurrentis, B. anserina and B. theileri are considered to have worldwide distribution, affecting humans, domestic birds and ruminants, respectively. Borrelia spp. associated with soft ticks are transmitted mainly by Ornithodoros ticks and thrive in endemic foci in tropical and subtropical latitudes. Nowadays, human cases of soft tick-borne relapsing fever remain neglected diseases in several countries, and the impact these spirochetes have on the health of wild and domestic animals is largely understudied. Human infection with RFGB is difficult to diagnose, given the lack of distinguishing clinical features (undifferentiated febrile illness). Clinically, soft tick or louse-borne relapsing fever is often confused with other etiologies, such as malaria, typhoid or dengue. In Latin America, during the first half of the twentieth century historical documents elaborated by enlightened physicians were seminal, and resulted in the identification of RFGB and their associated vectors in countries such as Mexico, Panama, Colombia, Venezuela, Peru and Argentina. Almost 80 years later, research on relapsing fever spirochetes is emerging once again in Latin America, with molecular characterizations and isolations of novel RFGB members in Panama, Bolivia, Brazil and Chile. In this review we summarize historical aspects of RFGB in Latin America and provide an update on the current scenario regarding these pathogens in the region. To accomplish this, we conducted an exhaustive search of all the published literature for the region, including old medical theses deposited in libraries of medical academies. RFGB were once common pathogens in Latin America, and although unnoticed for many years, they are currently the focus of interest among the scientific community. A One Health perspective should be adopted to tackle the diseases caused by RFGB, since these spirochetes have never disappeared and the maladies they cause may be confused with etiologies with similar symptoms that prevail in the region.

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Ornithodoros mimon is an argasid tick primarily associated with bats that also infest other animals including birds, opossums and humans. In this paper, we report the finding of an argasid species resembling O. mimon, which similarly may be found in human dwellings and parasitize humans in Brazil. We also provide molecular evidence that this argasid tick species may carry a rickettsial organism, whose pathogenicity remains unknown. A total of 16 ticks (two females, two males and 12 nymphs) were collected in the bedroom and in the attic of a human house, where cases of "insect" bites have been recurrent. These ticks were identified morphologically and genetically as Ornithodoros cf. mimon. Upon PCR testing, four of these ticks (one female and three nymphs) were positive for human blood and for a bacterium closely related to "Candidatus Rickettsia paranaensis". In conclusion, we report for the first time in Brazil an argasid tick species morphologically and genetically related to O. mimon, which feeds on humans and carry a rickettsial organism belonging to the spotted fever group. Further studies are needed to formally assess the taxonomic status of this tick species and also to investigate the pathogenicity of its associated rickettsial organism.

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In Brazil, 19 species of the genus Ornithodoros (Acari: Argasidae) have been reported. The medical and veterinary importance of Ornithodoros ticks has increased substantially in recent decades, with the discovery of various relapsing fever Borrelia infecting Ornithodoros ticks. Herein, argasid ticks were collected during 2019-2020 from caves, abandoned nests and homes in various regions of Ceará State, Brazilian semiarid-Caatinga biome. In total, 289 ticks were collected and identified into five species: Ornithodoros cavernicolous (176 specimens), Ornithodoros fonsecai (81), Ornithodoros mimon (12), Ornithodoros rietcorreai (4), and a fifth species provisionally retained as Ornithodoros sp. Ubajara. Tick identifications were corroborated by a phylogenetic analysis inferred using the 16S rRNA gene. To extend the molecular characterization, DNA samples were tested by an additional PCR assay targeting the nuclear Histone 3 (H3) gene. Because there were no H3 sequences of argasids in GenBank, we extended this PCR assay for additional Ornithodoros species, available in our laboratory. In total, 15 partial sequences of the H3 gene were generated for 10 Ornithodoros species, showing 0% intraspecific polymorphism, and 1.5-11.6% interspecific polymorphism. Phylogenetic analyses inferred segregated Ornithodoros sp. Ubajara as a potential novel species. Our results also highlight the potential of the H3 gene for deeper phylogenetic analyses of argasids. The present study provides new data for argasid ticks of the genus Ornithodoros in the Caatinga biome. Because some of these tick species are human-biting ticks, active surveillance for the incidence of human infection due to Ornithodoros-borne agents is imperative in the Caatinga biome.

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The present study analyzes the diversity of bacteria of the genus Rickettsia in ticks collected from wild mammals and vegetation at the Chamela Biological Station (EBCh), Jalisco, Mexico, a core area in the Chamela-Cuixmala Biosphere Reserve, which is characterized by the presence of tropical dry forest, one of the most threatened ecosystems in the world. Ticks were collected during April and November 2018 and 2019, determined to species, and subsequently processed for rickettsiae. Genomic DNA was extracted from each of 349 ticks (198 from mammals, 151 from vegetation) and screened for Rickettsia by targeting the gltA and ompA genes. Overall, 75 ticks (21.5%) were positive for rickettsiae (46 from mammals, 29 from vegetation). Through BLASTn and maximum likelihood analysis, four Rickettsia taxa were identified. Only Rickettsia amblyommatis had been previously recorded in the vicinity of the EBCh, and we confirm its presence in this reserve, associated with Amblyomma mixtum, Amblyomma cf. oblongoguttatum and Amblyomma parvum. Additionally, we record for the first time at EBCh the taxa Rickettsia parkeri strain Atlantic rainforest, which is known to cause spotted fever illness in humans, detected in Amblyomma ovale; Rickettsia bellii in A. parvum and Ornithodoros talaje; and an undescribed Rickettsia sp. in Ixodes sinaloa.

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Ticks of genus Ornithodoros are nidicolous parasites associated with a wide array of vertebrates. In humans, their bites cause hypersensitivity reactions and are capable to transmit pathogens of health concern. In the department of Córdoba, Caribbean region of Colombia, the first report of an Ornithodoros soft tick was made in 1980 by Betancourt, who described the collection of Ornithodoros talaje in human dwellings. Nevertheless, current the records of O. talaje made in South America have been questioned and likely correspond to misidentifications with morphologically similar species. Between October and December of 2020, we visited rural areas of four localities from three municipalities within the department of Córdoba: Cuero Curtido and Severá (municipality of Cereté), El Espanto (municipality of Planeta Rica), and Arroyo Negro (municipality of San Carlos). Search for soft ticks was performed in 46 human domiciles and peridomiciliary areas. We searched in areas frequented by domestic animals, inspecting cracks in the walls and fowl nests. Infestation by soft ticks was found in 13% (6/46) of visited houses. Overall, 215 ticks were collected (26 larvae, 144 nymphs and 45 adults) from nests of domestic birds or in the adjacent walls. Larvae, nymphs and adults were morphologically identified as Ornithodoros puertoricensis. Molecular identification of ticks was confirmed by sequencing the tick mitochondrial 16S gene of adults, pools of nymphs and larvae. Pairwise comparisons showed a 99% of identity with O. puertoricensis from Panama. This study reports for the first time O. puertoricensis associated with domestic fowl in rural dwellings in Colombia, and expands the geographical distribution of this tick species toward the Córdoba department. Importantly, local people described exposure to tick bites while sleeping in infested houses; therefore, the transmission of soft tick-borne pathogens is now of concern in the region.

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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.

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Bats have been implicated as reservoirs of relapsing fever group spirochaetes since the beginning of the last century. Recently, bat-associated spirochaetes have been reported as human pathogens. In 1968, a spirochaete was detected in blood of the bat Natalus tumidirostris captured inside the Macaregua cave, Colombia. Data on this microorganism were never published again. The aim of this study was to evaluate the presence of Borrelia DNA in blood from bats of Macaregua cave. We performed molecular analyses using a genus-specific real-time PCR targeting the 16S rRNA to detect DNA of Borrelia in blood samples from 46 bats captured in the Macaregua cave. Positive samples were submitted to a battery of PCRs aiming to amply Borrelia 16S rRNA, flaB, glpQ, p66, ospC, clpA, clpX, nifS, pepX, pyrG, recG, rplB and uvrA genes. Seventeen samples were positive for Borrelia after real-time PCR. With the exception of flaB gene, attempts to amplify further loci were unsuccessful. Nucleotide and amino acid divergences of four flaB haplotypes characterized from blood of Carollia perspicillata showed Borrelia burgdorferi sensu lato (Bbsl) as the most closely related group. A phylogenetic tree including 74 sequences of the genus confirmed this trend, since Borrelia genotypes detected in bats from Macaregua formed a monophyletic group basally positioned to Bbsl. Our results suggest that Borrelia genotypes characterized from bats roosting in the Macaregua cave might constitute a new taxon within the genus. This is the first molecular characterization of a Borrelia sp. in Colombia.

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We conducted a molecular survey for Borrelia spp. in Ornithodoros ticks previously reported as biting humans. We collected specimens in natural ecosystems and inside human dwellings in 6 states in Brazil. Phylogenetic analyses unveiled the occurrence of 4 putatively new species of relapsing fever group borreliae.

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Parasites are a selective force that shape communities and ecosystems. Hosts represent a food source, habitat, and a way to disperse. In recent years, investigations dealing with bats and their role as hosts to numerous parasitic organisms, including metazoan ectoparasites and endoparasites have increased, and soft ticks (Parasitiformes: Ixodida: Argasidae) are among the best known. In Mexico, 16 species of soft ticks associated with bats have been reported up to now, but there are no specific records of soft ticks parasitizing Leptonycteris yerbabuenae in the country. Herein, we record for the first time the presence of Ornithodoros dyeri parasitizing L. yerbabuenae and report an extension of its geographic distribution. The same tick species was also recorded from the California leaf-nosed bat (Macrotus californicus). Data on prevalence, mean intensity, mean abundance, tick identification, and possible scenarios of life cycle associations for O. dyeri and one of its hosts, L. yerbabuenae, are discussed.

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The Brazilian state of Maranhão is located in a transition area of the Amazon and Cerrado biomes, where there is a rich fauna of vertebrates. This study aimed to update the list of the ticks occurring in Maranhão, through a compilation of literature records and examination of three tick collections, plus the addition of unpublished collections of ticks from road-killed animals during recent years. Our results indicate that the tick fauna of Maranhão includes 26 species: seven in the family Argasidae (Antricola guglielmonei, Argas miniatus, Ornithodoros cavernicolous, Ornithodoros hasei, Ornithodoros mimon, Ornithodoros rietcorreai and Ornithodoros rudis); and 19 in the family Ixodidae (Amblyomma auricularium-provisional, Amblyomma cajennense sensu stricto, Amblyomma calcaratum, Amblyomma dissimile, Amblyomma geayi, Amblyomma longirostre, Amblyomma naponense, Amblyomma nodosum, Amblyomma oblongoguttatum, Amblyomma ovale, Amblyomma parvum, Amblyomma rotundatum, Amblyomma sculptum, Amblyomma triste, Dermacentor nitens, Ixodes luciae, Haemaphysalis juxtakochi, Rhipicephalus microplus, and Rhipicephalus sanguineus sensu lato). Eleven of the above species are reported for the first time in Maranhão. We consider previous reports of Ornithodoros talaje and Amblyomma pseudoconcolor in Maranhão as misidentification with O. hasei and A. auricularium, respectively. Until 1958, only 11 tick species were reported in Maranhão, with no additional reports until 2009. During 2010-2019, 15 additional species were reported. We also highlight the importance of ticks for public and veterinary health in Maranhão.

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Larvae of Ornithodoros knoxjonesi collected at five localities in three countries were studied using morphological and molecular methods to confirm this species' taxonomic validity. The larva of O. knoxjonesi is characterized as having 14 pairs of dorsal setae, eight pairs of ventral setae, plus a posteromedian seta; an elongate dorsal plate, tapered anteriorly; and a hypostome that is narrower near its midlength, with posteriorly projecting denticles. Although the larvae of O. knoxjonesi and Ornithodoros peropteryx are morphologically quite similar, the larva of O. knoxjonesi is characterized as having dorsal setae that are wider at the tip than at the base, while in O. peropteryx these setae are narrower at the tip than at the base; moreover, the dorsal setae are shorter in O. knoxjonesi (Al 0.037-0.065; Pl 0.035-0.059) than in O. peropteryx (Al 0.120-0.132; Pl 0.080-0.096). These species also differ in that O. knoxjonesi possesses only the Al seta on tarsus I, whereas O. peropteryx has both Al and Pl setae. And while both species have two setae on coxae I-III, in O. knoxjonesi the anterior seta is tapering and smooth and the posterior is fringed, while both setae are fringed in O. peropteryx. At the molecular level, based on a maximum likelihood analysis using approximately 400 bp of the mitochondrial 16S rDNA gene, O. knoxjonesi appears as an independent lineage, separated from O. peropteryx by a genetic distance of 16.28 %. Balantiopteryx plicata is a common host of O. knoxjonesi; however, in this work we report Pteronotus personatus and Pteronotus gymnonotus as new hosts of this tick species.

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Ornithodoros capensis sensu lato (s.l.) is a morphologically similar group of soft ticks that parasitizes mostly seabirds in continental and offshore territories worldwide. Ornithodoros capensis sensu stricto (s.s.) has been previously recorded in many islands and coastal localities along the American continent; however, some records from Central America remain obscure. In this work we performed morphological and molecular analyses on soft ticks collected in Coiba National Park, an archipelago located in the Pacific Ocean off the coast of Panama, confirming the occurrence of O. capensis s.s. in this country for the first time. In addition, a morphological examination of museum specimens collected in Costa Rica, and a further locality in Panama, confirmed that O. capensis s.l. is established in the former country, and that its distribution along Panamanian shores is likely larger.

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