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）是其分布南界马格里布地区针叶林的重要害虫。基于线粒体标记（mitochondrial markers）的前期研究显示，该物种的西部种群（pityocampa分支（clade））与东部马格里布种群（ENA分支（clade））之间存在显著遗传分化，两支的接触带（contact zone）位于阿尔及利亚境内。我们以阿尔及利亚境内的该蛾分布区为研究对象，同时使用线粒体标记（tRNA-cox2的648bp片段）与核标记（11个微卫星位点（microsatellite loci））开展研究。进一步针对线粒体分支间接触带的样带，我们使用更短的线粒体DNA片段与相同的微卫星位点开展了分析。结果表明，线粒体多样性呈现显著的地理结构，且两支间存在清晰的接触带。具体而言，pityocampa分支内部存在两个亚分支，而ENA分支未显现出进一步的遗传结构。微卫星分析则呈现出截然不同的分化模式，存在两个主要类群，且与线粒体分支并不重合。线粒体标记与核标记间的不一致性，大概率可通过性别偏向性扩散以及近期造林活动弥合了隔离种群间的阻隔这一现象来解释。