| Accurate identification of species is an important prerequisite for effective prevention and control of ticks and tick-borne diseases.In view of Haemaphysalis qinghaiensis,H.japonica,H.concinna and H.sulcate are common species of Haemaphysalis in northern China.Their morphological characteristics are very similar,and their distribution areas overlap.Among them,the female ticks of H.concinna and H.japonica,H.japonica and H.qinghaiens,H.sulcate and H.qinghaiens are often confused.At the same time,many gene sequences uploaded on Genbank with species misidentified.Therefore,this paper takes the above four closely related species of Haemaphysalis as the research objects,and systematic taxonomy research is carried out from the perspectives of micro-morphology and molecular biology for the first time.1.Morphological characteristics of the four Haemaphysalis were observed and analyzed using ultra-depth microscope and scanning electron microscope.This study updated the morphological characteristics that were not described before(such as the morphological features of H.sulcate larva and nymph,and microstructure characteristics of each species at each stage of development,etc.),inaccurate or wrong described.The scanning electron microscope images are added to make the classification characteristics more intuitive and clear.2.The keys to adult,nymphs and larvae of species were compiled for the first time.The typical identification points of the four tick species were analyzed in detail.3.16S rDNA,COI and ITS2 gene sequences were amplified.Combined with the information of Haemaphysalis from other countries and regions,the sequence alignment,genetic distance and phylogenetic analysis revealed their genetic relationship and taxonomic status in the genus Haemaphysalis.The results showed that the four Haemaphysalis can be clearly distinguished by the above three molecular markers;H.qinghaiensis and H.japonica had the closest taxonomic status,while H.sulcus and H.concinna had the farthest genetic relationship.Haemaphysalis contains two lineages,one of which is H.japonica,H.qinghaiensis and H.concinna,and the other is H.sulcate.The results of this study will be helpful to solve the problem that these closely related species are easily confused and difficult to identify.It also lay the foundation for building a more objective and natural classification system,and provide basic information for other researchers of ticks and tick-borne diseases. |
