Dermacentor abaensis(D.abaensis)is a tick species distributed only in Qinghai,Gansu,and other provinces of China.It is more harmful because it can carry pathogens such as Borrelia burgdorferi and Piroplasm.However,morphological descriptions and image data for this tick spe-cies are still insufficiently detailed,and data related to molecular markers such as COX 1 and ITS2 are still missing.The ticks were collected from the body surface of yaks in Diebu County,Gannan Tibetan Autonomous Prefecture,Gansu Province.The morphological characteristics of various parts of the ticks were carefully observed using a stereomicroscope ultra-depth-of-field system.At the same time,the total DNA of the tick body wall was extracted,then the primers for COX 1 and ITS2 genes were designed,and PCR amplification was performed before sequencing.The sequen-cing results were compared with related sequences in GenBank for homology analysis,and the phy-logenetic tree was constructed to provide a basis for accurate identification of this tick species.The results showed that the female ticks were subrounded.The basic capituli were rectangular in shape.The porose area was ovoid in shape,cornua short and blunt,palps thick and short,with a slightly pointed front end.A slightly rounded scutum,and the enamel color was slightly lighter towards the back.The cervial groove was short,and in deeply concave.The festoon was obvious.The peritreme was in comma-shaped.The trailing edge was slightly curved.The genital opening had a ala.The anus was located in the posterior quarter of the middle of the abdomen,and there is a semicircular anal groove surrounded.Male ticks were slightly elongated ovoid,with no porose area.The entire surface was covered with enamel color except the cornua.The genital opening was opposite to the coxall,and there is no ala.The anal groove was deeper,and the external spur of the coxa Ⅳ was narrower and longer.All other body characteristics are similar to those of female ticks.Based on the comparative analysis of COX 1 and ITS2 gene sequences and the construction of phylogenetic tree,it was found that D.abaensis is more closely related to Dermacentor nuttalli and Dermacentor marginatus than other Dermacentor spp.The results suggested that D.abaensis have unique mor-phological and molecular marker characteristics,and the combination of the two characteristics will make it easier to rapidly and accurately identify this tick species.

Dermacentor abaensis(D.abaensis)is a tick species distributed only in Qinghai,Gansu,and other provinces of China.It is more harmful because it can carry pathogens such as Borrelia burgdorferi and Piroplasm.However,morphological descriptions and image data for this tick spe-cies are still insufficiently detailed,and data related to molecular markers such as COX 1 and ITS2 are still missing.The ticks were collected from the body surface of yaks in Diebu County,Gannan Tibetan Autonomous Prefecture,Gansu Province.The morphological characteristics of various parts of the ticks were carefully observed using a stereomicroscope ultra-depth-of-field system.At the same time,the total DNA of the tick body wall was extracted,then the primers for COX 1 and ITS2 genes were designed,and PCR amplification was performed before sequencing.The sequen-cing results were compared with related sequences in GenBank for homology analysis,and the phy-logenetic tree was constructed to provide a basis for accurate identification of this tick species.The results showed that the female ticks were subrounded.The basic capituli were rectangular in shape.The porose area was ovoid in shape,cornua short and blunt,palps thick and short,with a slightly pointed front end.A slightly rounded scutum,and the enamel color was slightly lighter towards the back.The cervial groove was short,and in deeply concave.The festoon was obvious.The peritreme was in comma-shaped.The trailing edge was slightly curved.The genital opening had a ala.The anus was located in the posterior quarter of the middle of the abdomen,and there is a semicircular anal groove surrounded.Male ticks were slightly elongated ovoid,with no porose area.The entire surface was covered with enamel color except the cornua.The genital opening was opposite to the coxall,and there is no ala.The anal groove was deeper,and the external spur of the coxa Ⅳ was narrower and longer.All other body characteristics are similar to those of female ticks.Based on the comparative analysis of COX 1 and ITS2 gene sequences and the construction of phylogenetic tree,it was found that D.abaensis is more closely related to Dermacentor nuttalli and Dermacentor marginatus than other Dermacentor spp.The results suggested that D.abaensis have unique mor-phological and molecular marker characteristics,and the combination of the two characteristics will make it easier to rapidly and accurately identify this tick species.