RESUMO
Argasid systematics remains controversial with widespread adherence to the Hoogstraal (1985) classification scheme, even though it does not reflect evolutionary relationships and results in paraphyly for the main genera of soft ticks (Argasidae), namely Argas and Ornithodoros. The alternative classification scheme, proposed by Klompen and Oliver (1993), has problems of its own: most notably paraphyly of the subgenus Pavlovskyella and the controversial grouping together of the subgenera Alectorobius, Antricola, Carios, Chiropterargas, Nothoaspis, Parantricola, Reticulinasus and Subparmatus into the genus Carios. Recent phylogenetic analyses of 18S/28S rRNA sequences and mitochondrial genomes agree with the scheme of Klompen and Oliver (1993), with regard to the paraphyly of Pavlovskyella, placement of Alveonasus, Ogadenus, Proknekalia and Secretargas in the Argasinae and placement of Carios and Chiropterargas in the Ornithodorinae (Mans et al., 2019). The Carios clade and its constituent subgenera remain controversial, since the phylogenetic position of its type species Carios (Carios) vespertilionis Latreille, 1796 (formerly Argas vespertilionis) has not been determined with confidence. The current study aimed to resolve Carios sensu lato Klompen and Oliver, 1993, and Carios sensu stricto Hoogstraal, 1985, by determining and analysing phylogenetic nuclear and mitochondrial markers for C. (C.) vespertilionis. Both the nuclear and mitochondrial markers support placement of Carios s.s. within the subfamily Ornithodorinae, but to the exclusion of the clade that includes the 6 other subgenera that are part of Carios s.l. Klompen and Oliver (1993), namely Alectorobius, Antricola, Nothoaspis, Parantricola, Reticulinasus and Subparmatus. These 6 subgenera form a monophyletic clade that might be placed as new subgenera within the genus Alectorobius, or elevated to genera. Given the substantial differences in biology among these subgenera, we propose that these 6 subgenera be elevated to genera. Thus, we propose to modify the classification scheme of Mans et al. (2019) so that the subfamily Argasinae now has six genera, Alveonasus, Argas (subgenera Argas and Persicargas), Navis, Ogadenus, Proknekalia and Secretargas, and the subfamily Ornithodorinae has nine genera, Alectorobius, Antricola (subgenera Antricola and Parantricola), Carios, Chiropterargas, Nothoaspis, Ornithodoros (subgenera Microargas, Ornamentum, Ornithodoros, Pavlovskyella and Theriodoros), Otobius, Reticulinasus and Subparmatus (genera indicated in bold).
Assuntos
Argasidae/classificação , Genoma Mitocondrial , Animais , Argas/classificação , Argas/genética , Argas/crescimento & desenvolvimento , Argasidae/genética , Argasidae/crescimento & desenvolvimento , Feminino , Marcadores Genéticos , Larva/classificação , Larva/genética , Larva/crescimento & desenvolvimento , Ornithodoros/classificação , Ornithodoros/genética , Ornithodoros/crescimento & desenvolvimento , Filogenia , RNA Ribossômico 18S/análise , RNA Ribossômico 28S/análiseRESUMO
BACKGROUND: Increasing molecular evidence supports that bats and/or their ectoparasites may harbor vector-borne bacteria, such as bartonellae and borreliae. However, the simultaneous occurrence of rickettsiae in bats and bat ticks has been poorly studied. METHODS: In this study, 54 bat carcasses and their infesting soft ticks (n = 67) were collected in Shihezi City, northwestern China. The heart, liver, spleen, lung, kidney, small intestine and large intestine of bats were dissected, followed by DNA extraction. Soft ticks were identified both morphologically and molecularly. All samples were examined for the presence of rickettsiae by amplifying four genetic markers (17-kDa, gltA, ompA and ompB). RESULTS: All bats were identified as Pipistrellus pipistrellus, and their ticks as Argas vespertilionis. Molecular analyses showed that DNA of Rickettsia parkeri, R. lusitaniae, R. slovaca and R. raoultii was present in bat organs/tissues. In addition, nine of the 67 bat soft ticks (13.43%) were positive for R. raoultii (n = 5) and R. rickettsii (n = 4). In the phylogenetic analysis, these bat-associated rickettsiae clustered together with conspecific sequences reported from other host and tick species, confirming the above results. CONCLUSIONS: To the best of our knowledge, DNA of R. parkeri, R. slovaca and R. raoultii was detected for the first time in bat organs/tissues. This is also the first molecular evidence for the presence of R. raoultii and R. rickettsii in bat ticks. To our knowledge, R. parkeri was not known to occur in Asia. Our results highlight the need to assess rickettsial agents in a broader range of bat species and associated tick species.
Assuntos
Argas/genética , Quirópteros/microbiologia , Quirópteros/parasitologia , Rickettsia/isolamento & purificação , Infestações por Carrapato/veterinária , Animais , Argas/classificação , Argas/fisiologia , China , Intestinos/microbiologia , Intestinos/parasitologia , Rim/microbiologia , Rim/parasitologia , Fígado/microbiologia , Fígado/parasitologia , Pulmão/microbiologia , Pulmão/parasitologia , Filogenia , Rickettsia/classificação , Rickettsia/genética , Infestações por Carrapato/parasitologiaRESUMO
BACKGROUND: Parasites may actively seek for hosts and may use a number of adaptive strategies to promote their reproductive success and host colonization. These strategies will necessarily influence their host specificity and seasonality. Ticks are important ectoparasites of vertebrates, which (in addition to directly affecting their hosts) may transmit a number of pathogens. In Europe, three hard tick species (Ixodidae: Ixodes ariadnae, I. simplex and I. vespertilionis) and at least two soft tick species (Argasidae: Argas transgariepinus and A. vespertilionis) are specialized for bats. METHODS: Here we report data on the host range of these ticks and the seasonality of tick infestation on wild caught bats in south-east Europe. We collected 1803 ticks from 30 species of bats living in underground shelters (caves and mines) from Romania and Bulgaria. On the basis of tick-host associations, we tested several hypotheses on host-parasite evolutionary adaptations regulating host specificity, seasonality and sympatric speciation. RESULTS: We observed significant differences in host specificity and seasonality of abundance between the morphologically different bat specialist ticks (I. simplex and I. vespertilionis) likely caused by their host choice and their respective host-seeking behavior. The two highly generalist, but morphologically similar tick species (I. ariadnae and I. vespertilionis) showed temporal differences in occurrence and activity, thus exploiting significantly different host communities while occurring in geographical sympatry. CONCLUSIONS: We conclude that bat-specialist ticks show a wide range of adaptations to their hosts, with differences in specificity, seasonality of occurrence, the prevalence and intensity of infestation and all these contribute to a successful division of temporal niches of ticks sharing morphologically similar hosts occurring in geographical sympatry.
Assuntos
Argas/fisiologia , Quirópteros/parasitologia , Especificidade de Hospedeiro , Ixodes/fisiologia , Infestações por Carrapato/veterinária , Adaptação Fisiológica , Animais , Argas/classificação , Argas/genética , Bulgária , Quirópteros/classificação , Ixodes/classificação , Ixodes/genética , Filogenia , Romênia , Estações do Ano , Infestações por Carrapato/parasitologiaRESUMO
Ticks are important vectors and reservoirs of several zoonotic pathogens. Recently, both known and unknown tick-borne pathogens have emerged and re-emerged, causing unpredictable epidemics. In this study, 211 soft tick samples were collected from Tongliao and Alxa in Inner Mongolia, China. Tick species were identified by morphological and molecular biological analyses. Morphological analysis showed that there was no significant difference in surface features between ticks from the 2 areas. Cloning by polymerase chain reaction (PCR) and sequencing of the 16S rRNA gene showed that all ticks belonged to the species Argas persicus. Analysis using Genetyx software indicated that there was a limited degree of diversity between ticks from the 2 areas. Three base changes were detected in the 16S rRNA gene. We constructed phylogenetic trees using MEGA 6.0 software and showed that the ticks from the 2 areas might have evolved independently from species in other geographical areas. To assess the presence of Rickettsia, Streptococcus suis, and Staphylococcus aureus pathogens in tick samples, over 100 16S rRNA sequences belonging to these 3 pathogens were obtained from GenBank. We used CLC Sequence Viewer 7.0 to determine conserved sequences for the design of degenerate primers. Using standard PCR, we detected Rickettsia-specific genes, including 16S rRNA, 17KD, and ompB, in gDNA samples of ticks from Alxa. This study has laid a foundation for future studies on the biodiversity of ticks and for a new pathogen information database of ticks in local areas.
Assuntos
Argas/classificação , Argas/genética , Animais , Argas/anatomia & histologia , Argas/microbiologia , Galinhas , China , Clonagem Molecular , DNA/química , DNA/isolamento & purificação , Feminino , Variação Genética , Genótipo , Abrigo para Animais , Funções Verossimilhança , Masculino , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo Genético , RNA Ribossômico 16S/genética , Análise de Sequência de DNARESUMO
The systematics of the genera and subgenera within the soft tick family Argasidae is not adequately resolved. Different classification schemes, reflecting diverse schools of scientific thought that elevated or downgraded groups to genera or subgenera, have been proposed. In the most recent classification scheme, Argas and Ornithodoros are paraphyletic and the placement of various subgenera remains uncertain because molecular data are lacking. Thus, reclassification of the Argasidae is required. This will enable an understanding of soft tick systematics within an evolutionary context. This study addressed that knowledge gap using mitochondrial genome and nuclear (18S and 28S ribosomal RNA) sequence data for representatives of the subgenera Alectorobius, Argas, Chiropterargas, Ogadenus, Ornamentum, Ornithodoros, Navis (subgen. nov.), Pavlovskyella, Persicargas, Proknekalia, Reticulinasus and Secretargas, from the Afrotropical, Nearctic and Palearctic regions. Hard tick species (Ixodidae) and a new representative of Nuttalliella namaqua (Nuttalliellidae), were also sequenced with a total of 83 whole mitochondrial genomes, 18S rRNA and 28S rRNA genes generated. The study confirmed the utility of next-generation sequencing to retrieve systematic markers. Paraphyly of Argas and Ornithodoros was resolved by systematic analysis and a new species list is proposed. This corresponds broadly with the morphological cladistic analysis of Klompen and Oliver (1993). Estimation of divergence times using molecular dating allowed dissection of phylogeographic patterns for argasid evolution. The discovery of cryptic species in the subgenera Chiropterargas, Ogadenus and Ornithodoros, suggests that cryptic speciation is common within the Argasidae. Cryptic speciation has implications for past biological studies of soft ticks. These are discussed in particular for the Ornithodoros (Ornithodoros) moubata and Ornithodoros (Ornithodoros) savignyi groups.
Assuntos
Argasidae/classificação , Especiação Genética , Genoma Mitocondrial/genética , Animais , Argas/classificação , Argas/genética , Argasidae/genética , Classificação , Código de Barras de DNA Taxonômico , DNA Ribossômico/química , DNA Ribossômico/genética , Sequenciamento de Nucleotídeos em Larga Escala , Ornithodoros/classificação , Ornithodoros/genética , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Análise de Sequência de DNARESUMO
Argasid ticks (Acari: Argasidae) carry and transmit a variety of pathogens of animals and humans, including viruses, bacteria and parasites. There are several studies reporting ixodid ticks (Acari: Ixodidae) and associated tick-borne pathogens in Xinjiang, China. However, little is known about the argasid ticks and argasid tick-associated pathogens in this area. In this study, a total of 3829 adult argasid ticks infesting livestock were collected at 12 sampling sites of 10 counties in the Peripheral Oases, which carry 90% of the livestock and humans population, around the Tarim Basin (southern Xinjiang) from 2013 to 2016. Tick specimens were identified to two species from different genera by morphology and sequences of mitochondrial 16S rRNA and 12S rRNA were derived to confirm the species designation. The results showed that the dominant argasid ticks infesting livestock in southern Xinjiang were Ornithodoros lahorensis (87.86%, 3364/3829). Ornithodoros lahorensis was distributed widely and were collected from 10 counties of southern Xinjiang. Argas japonicus was collected from Xinjiang for the first time. In addition, we screened these ticks for tick-associated pathogens and showed the presence of DNA sequences of Rickettsia spp. of Spotted fever group and Anaplasma spp. in the argasid ticks. This finding suggests the potential role for Argas japonicus as a vector of pathogens to livestock and humans.
Assuntos
Anaplasma/isolamento & purificação , Argas/microbiologia , Ornithodoros/microbiologia , Rickettsia/isolamento & purificação , Anaplasma/classificação , Anaplasma/genética , Anaplasma/patogenicidade , Animais , Argas/classificação , Argas/genética , Bovinos , China , Vetores de Doenças , Mitocôndrias/genética , Ornithodoros/classificação , Ornithodoros/genética , Filogenia , RNA Ribossômico/classificação , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Rickettsia/classificação , Rickettsia/genética , Rickettsia/patogenicidade , Análise de Sequência de DNA , Ovinos , Infestações por Carrapato/parasitologia , Infestações por Carrapato/patologia , Infestações por Carrapato/veterináriaRESUMO
Ticks host a wide range of zoonotic pathogens and are a significant source of diseases that affect humans and livestock. However, little is known about the pathogens associated with bat ticks. We have collected ectoparasites from bat carcasses over a seven year period. Nucleic acids (DNA and RNA) were extracted from 296 ticks removed from bats and the species designation was confirmed in all ticks as Argas (Carios) vespertilionis. A subset of these samples (n = 120) were tested for the presence of zoonotic pathogens by molecular methods. Babesia species, Rickettsia spp., within the spotted fever group (SFG), and Ehrlichia spp. were detected in ticks removed from 26 bats submitted from 14 counties across England. The prevalence of Rickettsia spp. was found to be highest in Pipistrellus pipistrellus from southern England. This study suggests that the tick species that host B. venatorum may include the genus Argas in addition to the genus Ixodes. As A. vespertilionis has been reported to feed on humans, detection of B. venatorum and SFG Rickettsia spp. could present a risk of disease transmission in England. No evidence for the presence of flaviviruses or Issyk-Kul virus (nairovirus) was found in these tick samples.
Assuntos
Argas/genética , Babesia/genética , Quirópteros/microbiologia , Quirópteros/parasitologia , Rickettsia/genética , Infestações por Carrapato/veterinária , Zoonoses/epidemiologia , Animais , Argas/classificação , Babesia/classificação , Inglaterra , Genes Bacterianos , Interações Hospedeiro-Patógeno , RNA Ribossômico 16S/genética , Rickettsia/classificação , Infestações por Carrapato/epidemiologia , Zoonoses/microbiologiaRESUMO
This work showed protein analysis differentiates between the argasid tick species. Protein band numbers found in the different ticks were 15, 12, 8 and 14 bands of Argas persicus, A. hermanni, A. arborius, and the Ornithodorus savignyi respectively. The proteins with molecular weights 410 and 17 kD were found only in A. persicus. One protein with M.W 126 kD was found in O. savignyi. The absence of the protein with MW 88 kDa is only shown in A. hermanni. A. arborius, only eight protein bands are shown and the nonexistence proteins Mw were (181, 77, 21, 15.6 and 8.66 kDa) which are found in the other tick samples.
Assuntos
Argas/classificação , Argas/metabolismo , Proteínas de Artrópodes/metabolismo , Animais , Argas/química , Egito , Especificidade da EspécieRESUMO
The new locality of Argas reflexus in Warsaw, Poland is recorded. The ticks occur in the lof of apartment blocks, inhabited by pigeons. When the birds were removed by cleaning services, the ticks began to look for a new host and penetrate the flats. Some of the lodgers had been bitten by tick larvae and nymphs.
Assuntos
Argas/fisiologia , Mordeduras e Picadas/parasitologia , Columbidae/parasitologia , Insetos Vetores , Infestações por Carrapato/parasitologia , Infestações por Carrapato/veterinária , Animais , Argas/anatomia & histologia , Argas/classificação , Aves , Mordeduras e Picadas/complicações , Ecossistema , Interações Hospedeiro-Parasita , Humanos , Ninfa/classificação , Ninfa/microbiologia , Fatores de Risco , Infestações por Carrapato/epidemiologia , Urticária/etiologiaRESUMO
The female of Argas (Persicargas) keiransi Estrada-Peña, Venzal & González-Acuña (Acari: Argasidae) is described from specimens collected in the type locality in Chile. The female has a unique combination of characters in the dorsal cuticle and in the number and pattern of ventrolateral setae in the basis capituli. Additional features on tarsus I chaetotaxy and dorsal plate are provided for the larva of the species, as observed on flat specimens derived from engorged females collected in the type locality. Keys for the larvae of the New World Persicargas are provided as well as illustrations for prominent characters in hypostome and posterolateral setae. The mitochondrial 16S rDNA sequence of A. keiransi has been obtained, and an analysis of the phylogenetic relationships with other ticks is included. Phylogenetic analysis provides support for a Persicargas grouping of species, separated from species in Argas.
Assuntos
Argas/classificação , Argas/ultraestrutura , Filogenia , América , Animais , Argasidae/anatomia & histologia , Argasidae/classificação , Chile , Demografia , Feminino , Geografia , Larva/ultraestrutura , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Especificidade da EspécieRESUMO
The status of Argas persicus in Australia has been a matter of controversy for over 25 years. Although early records of A. persicus sensu stricto are common, a major revision of the genus indicated that these records refer to A. robertsi, first described in 1968 from northern Australia, and to an "undescribed" member of the complex occurring in the south. Here, we show that A. persicus sensu stricto does occur in southern Australia and is the only species of Argas in the area recorded from poultry. Another undescribed species belonging to the A. persicus complex, from crows' nests near Lake Eyre in South Australia, was also discovered. This information is of considerable epidemiological significance, as A. persicus sensu stricto is a major vector for a number of highly pathogenic diseases of poultry, not all of which have yet been recorded from Australia.
Assuntos
Argas/classificação , Infestações por Carrapato/veterinária , Animais , Argas/genética , DNA/genética , Vetores de Doenças , Doenças das Aves Domésticas/parasitologia , RNA/análise , RNA Mitocondrial , RNA Ribossômico/análise , Austrália do Sul/epidemiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologiaRESUMO
Ticks are ectoparasites of wide variety of vertebrates living in various types of environment all over the world. Morphological, biological, and physiological differences among tick species as well as among tick life stages are the result of tick adaptations to various life conditions. This paper presents morphological adaptations of tick tarsus to the hosts and the life conditions. The authors underline morphological differences of Haller's organ and pretarsus in four tick species: Argas reflexus (Fabricius, 1794), A. persicus (Oken, 1818), Dermacentor reticulatus (Fabricius, 1794), and Ixodes ricinus (Linnaeus, 1758).