目的 解析图兰扇头蜱（Rhipicephalus turanicus）线粒体全基因组的结构特征与系统发育关系，揭示不同地理种群之间的遗传分化，为进一步开展物种鉴定和系统发育分析等研究提供数据支撑。 方法 2023年8月，于山东省济宁市微山县马坡镇的一只家犬体表采集并鉴定图兰扇头蜱雄蜱1只，提取基因组DNA，采用Illumina测序平台二代测序技术进行测序，并利用Novoplasty软件进行序列组装，拼接完整的线粒体基因组全序列，使用MITOS软件对线粒体基因组进行初步功能注释。基于13个蛋白质编码基因（protein-coding gene，PCG）序列，应用最大似然法构建系统进化树。 结果 测序结果显示，图兰扇头蜱线粒体基因组全长为14 718 bp（GenBank登录号：PV416795），由13个PCG、22个转运RNA基因、2个核糖体RNA和2个非编码区（NCR）组成。线粒体基因组基因之间存在重叠或基因间隔区，碱基组成呈现明显A + T偏向性。PCG以ATA、ATC、ATG和ATT等4种典型的ATN序列作为起始密码子，TAA、TAG、TA、T为终止密码子。在22个tRNA基因二级结构中，除trnC、trnF、trnS1缺少二氢尿嘧啶臂（DHU臂）和二氢尿嘧啶环（DHU环）导致不能形成完整的三叶草结构外，其余均能形成典型的三叶草结构。系统进化分析表明，本研究采集的山东图兰扇头蜱与北京种群（登录号：OM368330）、新疆种群（登录号：KY996841、NC035946、OM368326）共同聚为一支，并与来自以色列（登录号：OQ184023）和沙特阿拉伯（登录号：PP919886）的种群共同构成一个强支持的单系分支。不同地理种群图兰扇头蜱聚为同一高度支持的系统发育分支，表明其具有较强的遗传保守性，同时也显示出一定的地域性遗传分化趋势。 结论 本研究获得了山东图兰扇头蜱线粒体基因组全序列，符合硬蜱科线粒体基因组特征，不同地理种群间存在潜在的遗传分化趋势。

Objective To decipher the mitochondrial genome structure and phylogenetic relationships of Rhipicephalus turanicus and investigate the genetic differentiation among different geographical populations of R. turanicus, so as to provide data supports to species identification and phylogenetic analysis. Methods A male R. turanicus tick was collected and identified from the body surface of a domestic dog in Mapo Township, Weishan County, Jining City, Shandong Province on August 2023, and genomic DNA was extracted from the tick for second-generation sequencing on an Illumina high-throughput platform. The complete mitochondrial genome of R. turanicus was assembled using Novoplasty software and the functions of the complete mitochondrial genome were preliminarily annotated with the MITOS software. In addition, phylogenetic trees were constructed using the maximum likelihood method based on the sequences of 13 protein-coding genes (PCGs). Results Second-generation sequencing showed that the complete mitochondrial genome of R. turanicus was 14 718 bp in length (GenBank accession No.: PV416795), which was consisted of 13 PCGs, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and 2 non-coding regions (NCRs). The complete mitochondrial genome contained overlapping regions or intergenic regions, and the base composition exhibited a clear A + T preference. The PCGs initiated with four typical start codons ATN (ATA, ATC, ATG, and ATT), and terminated with stop codons TAA, TAG, TA and T. Among the secondary structures of 22 tRNA gene, all formed a typical cloverleaf structure except for trnC, trnF, and trnS1, which lacked the dihydrouracil (DHU) arm and DHU loop, resulting in failure in formation of a complete cloverleaf structure. Phylogenetic analysis revealed that the R. turanicus sampled from Shandong Province in this study was clustered with tick populations from Beijing (GenBank accession No.: OM368330) and Xinjiang (GenBank accession No.: KY996841, NC035946, OM368326) into the same clade branch, and was grouped into a strongly supported monophyletic clade with populations from Israel (GenBank accession No.: OQ184023) and Saudi Arabia (GenBank accession No.: PP919886). The R. turanicus populations from different geographic regions were clustered into a highly supported phylogenetic clade, suggesting a high degree of genetic conservation and a tendency towards regional genetic differentiation. Conclusion The complete mitochondrial genome sequence of R. turanicus from Shandong Province has been obtained, which conforms to the mitochondrial genome characteristics of the Ixodidae family, and there is a tendency towards potential genetic differentiation among different geographic populations of R. turanicus.