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）类群在分类学上属于疑难类群——过去一个世纪间该类群已历经多次修订，但至今仍未解决分类学不确定性问题。本研究利用大量微卫星标记（microsatellite markers），对该名义物种开展了首次严谨可靠的遗传分析。本研究采用多种方法，对物种界定中常用的操作标准进行了验证，涵盖基因型聚类、生殖隔离/生殖凝聚以及单系性（monophyly）。基于研究结果，我们认定当前被认可的北美火蚁物种均为演化独立的类群；此外，我们证实了沙漠火蚁S. aurea与S. amblychila的推定姐妹群关系。然而，在名义物种的分类边界内，至少存在两个遗传分化的种群：包括西部型S. xyloni以及分布于美国加利福尼亚州科切拉谷的特有S. aurea种群。这表明当前的分类体系未能完全涵盖该类群的物种级多样性。本研究为该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，奠定了分子基础。