title: DNA sequence variation in Dermacentor hunteri and estimated phylogenies of Dermacentor spp. (Acari: Ixodidae) in the New World.
abstract: The genus Dermacentor is represented by 12 species in the New World. We sequenced a 300-bp portion of the mitochondrial 16S ribosomal DNA gene for 28 individual ticks representing 9 of these species and analyzed their phylogenetic relationships. Maximum parsimony, distance (neighbor-joining), and maximum likelihood were all used to resolve tree topologies. Eleven specimens of Dermacentor hunteri Bishopp representing populations across the tick's entire geographic range showed negligible genetic variation, with only single base-pair differences between each of 5 haplotypes. We found high degrees of bootstrap support (66-86%) for monophyly of the genus, but variable support for monophyly of species within the genus. D. hunteri, D. occidentalis Marx, and D. variabilis (Say) each resolved as a monophyletic taxon (79-99% support). D. andersoni Stiles and D. parumapertus Neumann formed a paraphyletic clade (99% support). D. albipictus Packard showed substantial intraspecific variation and warrants further investigation. D. imitans Warburton was distinct from all other Dermacentor spp. on all trees.
authors.affiliation: Department of Veterinary Pathology, Microbiology and Immunology, University of California, Davis 95616-8739, USA.
authors.forename: P R
authors.initials: PR
authors.lastname: Crosbie
authors.forename: W M
authors.initials: WM
authors.lastname: Boyce
authors.forename: T C
authors.initials: TC
authors.lastname: Rodwell
mesh_terms: D000818:Animals; D001483:Base Sequence; D004272:DNA, Mitochondrial / Q000235:genetics; D003870:Dermacentor / Q000145:classification* / Q000235:genetics*; D019143:Evolution, Molecular; D014644:Genetic Variation; D008297:Male; D008800:Mexico; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D015206:Southwestern United States
chemical_list: D004272:DNA, Mitochondrial; D012336:RNA, Ribosomal, 16S