A new argasid species, belonging to the subgenus Ornithodoros , namely, Ornithodoros ( Ornithodoros ) huajianensis was described for the first time based on the females, males and nymphs. The morphological features of each stage in the life cycle are unique, making identification easy, but are similar to other species of the subgenus Ornithodoros . The new species was diagnosed by the broad rectangular tongue and triangular tongue-shaped posterior lip in the male genital apron, a shallow camerostome with definite folds and smaller mammillae with single seta mixed with larger ones in nymph and adults. The new species had been collected from the Mongolian marmots Marmota bobak sibirica in Huajian village, Gulang county, Gansu province, China. Data on the phylogenic position, hosts and geographic distribution are also provided.

BackgroundA wide range of bacterial pathogens have been identified in ticks, yet the diversity of viruses in ticks is largely unexplored.MethodsHere, we used metagenomic sequencing to characterize the diverse viromes in three principal tick species associated with pathogens, Haemaphysalis concinna, Dermacentor silvarum, and Ixodes persulcatus, in North China.ResultsA total of 28 RNA viruses were identified and belonged to more than 12 viral families, including single-stranded positive-sense RNA viruses (Flaviviridae, Picornaviridae, Luteoviridae, Solemoviridae, and Tetraviridae), negative-sense RNA viruses (Mononegavirales, Bunyavirales, and others) and double-stranded RNA viruses (Totiviridae and Partitiviridae). Of these, Dermacentor pestivirus-likevirus, Chimay-like rhabdovirus, taiga tick nigecruvirus, and Mukawa virus are presented as novel viral species, while Nuomin virus, Scapularis ixovirus, Sara tick-borne phlebovirus, Tacheng uukuvirus, and Beiji orthonairovirus had been established as human pathogens with undetermined natural circulation and pathogenicity. Other viruses include Norway mononegavirus 1, Jilin partitivirus, tick-borne tetravirus, Pico-like virus, Luteo-like virus 2, Luteo-likevirus 3, Vovk virus, Levivirus, Toti-like virus, and Solemo-like virus as well as others with unknown pathogenicity to humans and wild animals.ConclusionIn conclusion, extensive virus diversity frequently occurs in Mononegavirales and Bunyavirales among the three tick species. Comparatively, I. persulcatus ticks had been demonstrated as such a kind of host with a significantly higher diversity of viral species than those of H. concinna and D. silvarum ticks. Our analysis supported that ticks are reservoirs for a wide range of viruses and suggested that the discovery and characterization of tick-borne viruses would have implications for viral taxonomy and provide insights into tick-transmitted viral zoonotic diseases.

Objective: Coxiella burnetii and Coxiella-like endosymbionts (CLEs) have been widely discovered in various ticks, animals, and even human beings. To estimate the possible origin of C. burnetii and its relatives CLEs, the prevalence of C. burnetii and CLEs has been intensively surveyed all over the world. Method: In the present study, the possible infection of C. burnetii and CLEs in host-seeking Haemaphysalis concinna was performed with meta-transcript analysis with tick specimens harvested from Mudanjiang City, Heilongjiang province, China. The meta-transcript results were subsequently confirmed by the specific sequence of partial 16S rRNA. Results: A total of three arrays of gene transcripts were harvested, including pyrophosphate-fructose 6-phosphate 1-phosphotransferase-eda-thiol-disulfide isomerase and thioredoxin-greA, carB-carA-DnaJ-DnaK-grpE-ppnk, ropC-ropB, and ubiA-non-canonical purine NTP pyrophosphatase-hemK-prfA, which suggest the infection of Candidatus Coxiella mudorwiae in H. concinna. The high identity of the 16S rRNA gene of Candidatus C. mudorwiae achieved in our study strongly supports our meta-transcripts analysis. Conclusion: The prevalence of Candidatus C. mudorwiae in hard ticks has been discovered in China. More detailed surveys are imperative to clarify the emergence of CLEs and their implication in the epidemiologic characteristics of Q fever.

Genus Rickettsia associated to blood-feeding arthropods are usually pathogenic when transmitted to vertebrates. These species include the agents of acute human disease such as typhus and Rocky Mountain spotted fever. However, many other Rickettsia have been uncovered with uncertain pathogenic to vertebrates in recent surveys. It is therefore perhaps more appropriate to consider these Rickettsiaas endosymbionts that are transmitted vertically in invertebrates, and secondarily as pathogens of vertebrates. Rickettsia canadensis, an ancestor species in genus Rickettsia, had been well characterized for its peculiar genome size and genes’ contents bridging the pathogenic Rickettsiaand non-pathogenic ones. However, there is few research on the ancient rickettsia species in China which may seriously influence our pursue for the evolutionary nature of Rickettsia in China. In the present study, R. canadensis was detected from Ixodes persulcatusticks from forest areas of both Heilongjiang province and Inner Mongolia Autonomous Region in northern China. The molecular evidences from both 16S rRNA gene and 3 arrays of gene transcripts strongly indicated the natural infection of R. canadensis occurs in Ixodid ticks in China. The gene transcripts including rpoB-rpoC-rpoC/160KDa-leucyl aminopeptidase-hypothetical protein-leucyl aminopeptidase-aspartate tRNA ligase, RlmE-Omp 1-Peptidase M50-nusB, dnaK-dnaJ-ChaBfamily protein-BamD-RecN-Carboxypeptidase M32 revealed from I. persulcatus suggested the intensive interactions between R. canadensis and. host ticks, which would provide scientific clues to highlight the possible evolutionary trajectory of Rickettsia species in China.