Abstract
BackgroundMany tick species have great morphological similarity and are thus grouped into species complexes. Molecular methods are therefore useful in the classification and identification of ticks. However, little is known about the genetic diversity of hard ticks in China, especially at the subspecies level. Tengchong is one of the epidemic foci of tick-borne diseases in China, but the tick species inhabiting the local area are still unknown.MethodsEighteen villages in Tengchong County, China, were selected for sampling carried out from September to October 2014. Infesting hard ticks were removed from the body surface of domestic animals and questing ticks were collected from grazing fields. After morphological identification, molecular characteristics of each tick species were analyzed based on both 16S rRNA and cytochrome c oxidase subunit 1 (cox1) gene fragments.ResultsSix tick species were identified based on morphology: Rhipicephalus microplus, R. haemaphysaloides, Ixodes ovatus, Haemaphysalis longicornis, H. shimoga and H. kitaokai. Phylogenetic analysis using the cox1 gene revealed that R. microplus ticks from the present study belong to clade C. For tick samples of both R. haemaphysaloides and I. ovatus, three phylogenetic groups were recognized, and the intergroup genetic distances exceeded the usual tick species boundaries. Haemaphysalis longicornis ticks were clustered into two separate clades based on the cox1 gene. For ticks from both H. shimoga and H. kitaokai, two phylogenetic groups were recognized based on the phylogenetic analysis of the 16S rRNA gene, and the intergroup genetic distances also exceeded the known boundaries for closely related tick species.ConclusionsAccording to molecular analyses, new species or subspecies closely related to R. haemaphysaloides, I. ovatus, H. shimoga and H. kitaokai probably exist in the China-Myanmar border Tengchong County, or these ticks form species complexes with highly divergent mitochondrial lineages. Morphological comparisons are warranted to further confirm the taxonomic status of these tick species.
Highlights
Many tick species have great morphological similarity and are grouped into species complexes
Ixodes ovatus and H. longicornis were collected only from goats, R. microplus ticks were collected from both goats and cattle, and R. haemaphysaloides were found on all three animal species (Table 2)
Several tick species were identified based on morphology, including R. microplus, R. haemaphysaloides, I. ovatus, H. longicornis, H. shimoga and H. kitaokai
Summary
Many tick species have great morphological similarity and are grouped into species complexes. Little is known about the genetic diversity of hard ticks in China, especially at the subspecies level. Hard ticks (Acari: Ixodidae) are obligate blood-sucking parasitic arthropods which can infest reptiles, birds and mammals [1]. They transmit a wide range of pathogens of both veterinary and medical importance, including bacteria, viruses, protozoa, etc. At least 117 tick species from seven genera have been reported in China [5]. The reported number of tick-borne infections has increased in this country. Since 1982, more than 30 emerging tick-borne agents have been recognized [1, 6,7,8,9], including severe fever with thrombocytopenia syndrome virus, Borrelia burgdorferi (sensu lato), Babesia spp., the
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
