Lone star ticks, Amblyomma americanum L. (Acari: Ixodidae), infest multiple hosts such as birds, and mammals of various sizes (rodents to white-tailed deer) and can harbor human pathogens such as Borrelia lonestari and Ehrlichiosis chaffeensis. The population structure of 251 A. americanum ticks, collected from canines and two white-tailed deer in six Arkansas ecoregions, was examined using DNA sequences of a 247-bp region of the mitochondrial DNA ribosomal RNA 16S gene. Of the 247 nucleotide characters, 26 were variable. Thirty-three haplotypes were identified of which 25 haplotypes occurred once (10%). The most common haplotype was Aa25, occurring in 60% of the samples and found in all six ecoregions. The excess of low frequency haplotypes combined with the overall negative Tajima's D and Fu and Li statistics suggests population expansion. Phylogenetic relationships of the 33 A. americanum haplotypes were constructed with other Amblyomma species and identified A. americanum as a monophyletic species with two groups. The patterns of high nucleotide and haplotype diversity found in this study suggests that the A. americanum population is expanding perhaps due to its ability to survive in a variety of habitats and feed on multiple hosts. Given the gene flow in Arkansas, the spread of acaricide resistance and pathogens may be rapid.
Translator Disclaimer
ACCESS THE FULL ARTICLE
It is not available for individual sale.
This article is only available to subscribers.
It is not available for individual sale.
It is not available for individual sale.
Journal of Medical Entomology
Vol. 47 • No. 2
March 2010
Vol. 47 • No. 2
March 2010
16S mitochondrial rDNA
Amblyomma americanum
population genetics