Data from: Comparative phylogeography of the plateau zokor (Eospalax baileyi) and its host-associated flea (Neopsylla paranoma) in the Qinghai-Tibet Plateau

Background: Specific host-parasite systems often embody a particular co-distribution phenomenon, in which the parasite’s phylogeographic pattern is dependent on its host. In practice, however, both congruent and incongruent phylogeographic patterns between the host and the parasite have been reported. Here, we compared the population genetics of the plateau zokor (Eospalax baileyi), a subterranean rodent, and its host-associated flea species, Neopsylla paranoma, with an aim to determine whether the two animals share a similar phylogeographic pattern. Results: We sampled 130 host-parasite pairs from 17 localities in the Qinghai-Tibet Plateau (QTP), China, and sequenced a mitochondrial DNA (mtDNA) segment (~2,500 bp), including the complete COI and COII genes. We also detected 55 zokor and 75 flea haplotypes. AMOVA showed that the percentage of variation among the populations of zokors constituted 97.10%, while the within population variation was only 2.90%; for fleas, the values were 85.68% and 14.32%, respectively. Moreover, the flea Fst (fixation index) values were significantly smaller than in zokor. Although the Fst values between zokors and fleas were significantly and positively correlated (N =105, R =0.439, p =0.000), only a small amount (R2= 0.19) of the flea Fst variations could be explained by the zokor Fst variations. The two animals showed very distinct haplotype network structures from each other while co-phylogenetic analyses were unable to reject the hypothesis of an independence of speciation events. Conclusions: Zokors and fleas have very distinct population genetic patterns from each other, likely due to the influence of other sympatrically-distributed vertebrates on the transmission of fleas.

背景：特定的宿主-寄生虫体系往往呈现出特有的共分布现象，即寄生虫的系统地理格局依赖于其宿主。但已有研究表明，宿主与寄生虫之间既存在系统地理格局一致的情况，也存在二者格局不一致的案例。本研究以地下啮齿类动物高原鼢鼠（Eospalax baileyi）及其体表寄生的异新蚤（Neopsylla paranoma）为研究对象，通过比较二者的种群遗传学特征，旨在明确二者是否具有相似的系统地理格局。
结果：本研究在中国青藏高原（Qinghai-Tibet Plateau, QTP）的17个采样点共获取130组宿主-寄生虫配对样本，对包含完整COI基因与COII基因的线粒体DNA（mtDNA）片段（约2500 bp）进行了测序。共检测到55个高原鼢鼠单倍型与75个蚤类单倍型。分子方差分析（Analysis of Molecular Variance, AMOVA）结果显示，高原鼢鼠种群间的遗传变异占比达97.10%，种群内遗传变异仅为2.90%；而蚤类的对应数值分别为85.68%与14.32%。此外，蚤类的Fst（固定指数，fixation index）值显著低于高原鼢鼠。尽管高原鼢鼠与蚤类的Fst值呈显著正相关（N=105，R=0.439，p=0.000），但高原鼢鼠的Fst变异仅能解释蚤类Fst变异中极小一部分（R²=0.19）。二者的单倍型网络结构差异显著，而共系统发育分析无法拒绝“物种形成事件独立”的假说。
结论：高原鼢鼠与其寄生蚤类的种群遗传模式存在显著差异，这一现象可能源于同域分布的其他脊椎动物对蚤类传播过程的影响。