title: Dermacentor everestianus Hirst, 1926 (Acari: Ixodidae): phylogenetic status inferred from molecular characteristics.
abstract: Dermacentor everestianus Hirst, 1926, is only reported in Northwestern China and Nepal. Few researches about this species have been involved, especially for molecular characteristics. The taxonomy studies of D.everestianus are mainly based on morphological features, and its taxonomic status is an ongoing controversy. To clarify the molecular characteristics and phylogenetic status of D.everestianus and other related species, the sequences of mitochondrial 16S ribosomal DNA (rDNA) and cox1 fragments were analyzed in the present study. Analysis of 16S rDNA and cox1 sequences showed 99.3-100% identity within D.everestianus individuals, with the genetic divergence among them was 0-0.0086. The interspecific distance of 16S rDNA and cox1 between D.everestianus and some other Palaearctic species including D. silvarum, D. nuttalli, and D. marginatus was much smaller than that between D.everestianus and Nearctic Dermacentor ticks (D.albipictus, D.nitens, and D.variabilis). Such relationships of these ticks were also verified in the phylogenetic analysis. Two major clades were recovered within Dermacentor spp. with more than 90% bootstrap support in the phylogenetic trees. D.everestianus together with D.silvarum, D.nuttalli, and D.marginatus were included in the clade I (Eurasia lineage). Other analyzed tick species including D.variabilis, D.nitens, and D.albipictus formed clade II, which are distributed in Nearctic realm. These indicated that the genus Dermacentor was at least composed of two lineages. Thus, further researches including additionally molecular markers on all Dermacentor species globally should be taken to precisely resolve relationships within Dermacentor.
authors.affiliation: State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou, Gansu, 730046, People's Republic of China, chenze@caas.cn.
authors.forename: Ze
authors.initials: Z
authors.lastname: Chen
authors.forename: Youquan
authors.initials: Y
authors.lastname: Li
authors.forename: Qiaoyun
authors.initials: Q
authors.lastname: Ren
authors.forename: Jin
authors.initials: J
authors.lastname: Luo
authors.forename: Zhijie
authors.initials: Z
authors.lastname: Liu
authors.forename: Xun
authors.initials: X
authors.lastname: Zhou
authors.forename: Guangyuan
authors.initials: G
authors.lastname: Liu
authors.forename: Jianxun
authors.initials: J
authors.lastname: Luo
authors.forename: Hong
authors.initials: H
authors.lastname: Yin
mesh_terms: D000818:Animals; D001483:Base Sequence; D002681:China; D051545:Cyclooxygenase 1 / Q000235:genetics; D004272:DNA, Mitochondrial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D003870:Dermacentor / Q000145:classification* / Q000235:genetics; D005260:Female; D014644:Genetic Variation; D008297:Male; D008969:Molecular Sequence Data; D009390:Nepal; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA / Q000662:veterinary; D012756:Sheep; D012757:Sheep Diseases / Q000469:parasitology*; D013984:Tick Infestations / Q000469:parasitology / Q000662:veterinary*
chemical_list: D004272:DNA, Mitochondrial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D051545:Cyclooxygenase 1