Molecular Characterization of Hard Ticks Infesting Camels in the Northern Region of Saudi Arabia Using the Barcoding Gene, Mitochondrial Cytochrome oxidase subunit I

The present study aimed to molecularly identify and characterize the hard ticks infesting camels from the northern region (Ha'il province) of Saudi Arabia using the mitochondrial barcoding gene cytochrome oxidase subunit I (COI). The sequences of tick samples from camels in three regions of Ha'il were aligned with those previously reported from different geographic regions, revealing nine haplotypes, of which six were newly described in this study for the first time. These haplotypes were used to determine their phylogenetic relationships using the maximum likelihood method, displaying two distinct clades corresponding to Hyalomma dromedarii and H. impeltatum. Moreover, the haplotypes showing the highest homology with those deposited in NCBI-GenBank from different geographic regions, including Saudi Arabia, were obtained and combined to determine their phylogenetic relationships among them. The results showed that the haplotypes belonging to two clades were grouped with those previously determined as H. dromedarii and H. impeltatum. Moreover, the presence of H. scupense (syn. H. detritum) together with H. impeltatum suggests possible asymmetrical hybridization and mitochondrial introgression between these species. H. scupense infesting different mammal species apart from camels were also clustered in a different clade, indicating the presence of different lineages of this species that show different host specificities.

Automated summary

The present study used the mitochondrial barcoding gene COI to identify and characterize hard ticks infesting camels in Ha'il province, Saudi Arabia. Nine haplotypes were found, with six being newly described. Phylogenetic analysis revealed two distinct clades corresponding to H. dromedarii and H. impeltatum. The presence of H. scupense together with H. impeltatum suggests possible asymmetrical hybridization and mitochondrial introgression between these species.