Data from: Genetic analyses reveal cryptic diversity in the native North American fire ants (Hymenoptera: Formicidae: Solenopsis)

The native North American fire ants (Solenopsis) comprise a difficult group taxonomically that has undergone multiple revisions in the past century yet remains in a state of taxonomic uncertainty. In this study, we utilized a large set of microsatellite markers to conduct the first robust genetic analysis of the nominal species. Our approach used a variety of methods to test operational criteria commonly employed in species delimitation, including genotypic clustering, reproductive isolation/cohesion, and monophyly. We conclude from our results that the recognized North American fire ant species represent evolutionarily independent entities and, moreover, we confirm the presumed sister status of the desert fire ants, S. aurea and S. amblychila. However, the presence of at least two genetically divergent populations within the nominal species boundaries, including a western form of S. xyloni and a distinct population of S. aurea endemic to the Coachella Valley of California, suggests that the current taxonomy does not fully capture the species-level diversity in this group. Our study provides the molecular foundation for future integrated studies of the taxonomy and evolution of this scientifically and economically important group of insects.原产于北美洲的火蚁属（Solenopsis）昆虫是一个分类学疑难类群——尽管在过去一个世纪间已历经多次分类修订，但其分类学不确定性仍未得到妥善解决。本研究借助一套大规模微卫星（microsatellite）标记，首次对该名义物种开展了严谨可靠的遗传分析。我们采用多种方法，对物种界定中常用的多项操作标准进行了检验，包括基因型聚类、生殖隔离/生殖凝聚性以及单系性（monophyly）。基于研究结果，我们认定当前已被命名的北美火蚁物种均为演化上独立的实体；此外，我们证实了此前推测的沙漠火蚁类群中金黄火蚁（S. aurea）与钝唇火蚁（S. amblychila）的姐妹群关系。然而，在名义物种的分类边界内，至少存在两个遗传分化显著的种群：包括西部型木火蚁（S. xyloni）以及加州科切拉谷地特有的一个独特金黄火蚁（S. aurea）种群，这表明当前的分类系统未能完全涵盖该类群的物种级多样性。本研究为这一兼具科学与经济重要性的昆虫类群的分类学与演化综合研究，奠定了坚实的分子基础。