Data from: Genetic differentiation of the pine processionary moth at the southern edge of its range: contrasting patterns between mitochondrial and nuclear markers

The pine processionary moth (Thaumetopoea pityocampa) is an important pest of coniferous forests at the southern edge of its range in Maghreb. Based on mitochondrial markers, a strong genetic differentiation was previously found in this species between western (pityocampa clade) and eastern Maghreb populations (ENA clade), with the contact zone between the clades located in Algeria. We focused on the moth range in Algeria, using both mitochondrial (a 648 bp fragment of the tRNA-cox2) and nuclear (11 microsatellite loci) markers. A further analysis using a shorter mtDNA fragment and the same microsatellite loci was carried out on a transect in the contact zone between the mitochondrial clades. Mitochondrial diversity showed a strong geographical structure and a well-defined contact zone between the two clades. In particular, in the pityocampa clade, two inner subclades were found whereas ENA did not show any further structure. Microsatellite analysis outlined a different pattern of differentiation, with two main groups not overlapping with the mitochondrial clades. The inconsistency between mitochondrial and nuclear markers is probably explained by sex-biased dispersal and recent afforestation efforts that have bridged isolated populations.松异舟蛾（Thaumetopoea pityocampa）是马格里布地区分布南缘针叶林的重要害虫。既往基于线粒体分子标记的研究发现，该物种的西部种群（松异舟蛾支系，pityocampa clade）与东部马格里布种群（东马格里布支系，Eastern Maghreb clade，简称ENA支系）之间存在显著遗传分化，两支系的接触带位于阿尔及利亚境内。本研究聚焦阿尔及利亚境内的该蛾类分布范围，同时采用线粒体（tRNA-cox2的648bp片段）与核基因组（11个微卫星位点）标记开展分析。此外，针对线粒体支系间的接触带样带，本研究使用更短的线粒体DNA片段与同一套微卫星位点进行了补充分析。结果显示，线粒体多样性呈现强烈的地理结构特征，且两支系间存在清晰的接触带；具体而言，松异舟蛾支系内部可划分为两个亚支系，而ENA支系未表现出任何进一步的遗传结构。微卫星分析则揭示了截然不同的分化模式，存在两个与线粒体支系并无重叠的主要群体。线粒体标记与核标记之间的不一致性，大概率可通过性别偏向扩散以及近年为连通隔离种群所开展的造林活动得到解释。