show Abstracthide AbstractSingle nucleotide polymorphisms (SNPs) were obtained through ddRAD sequencing in the Gulf Coast Tick (Amblyomma maculatum). These were used to assess the population structure of the species at a variety of spatial scales. The main purposes was to analyze the difference between two geographically isolated morphotypes (morphotypes II and III) to determine whether they represented distinct species. We also used the sequences to assess the population structure within each morphotype. Lastly, the population genetic statistics from the SNP data were compared to data from 6 microsatellite markers, representing the first comparison of microsatellites and SNPs in ticks. This work has relevance for understanding the evolution of ticks in North America, as well as the evolution of the diseases they carry.