High-Resolution Population Genetic Structure of Tawny Crazy Ant (Nylanderia fulva Mayr: Hymenoptera: Formicidae) from the Origin in South America and Introduced Regions of the United States

Background The tawny crazy ant (Nylanderia fulva Mayr) is native to South America and was first reported in the continental United States (US) in 1938. It was not until the 1990s in Florida and 2000s in Texas that this ant was considered a serious pest in the US. Tawny crazy ant (TCA) is currently considered an invasive pest in six US states and this ant’s invasion success is attributed in part to a unicolonial nature, multiple queens per nest, natural enemies release in the invasive range, and ability to detoxify venom from other competitor ant species. A limited number of low-density molecular markers have previously shown little genetic differentiation among TCA populations across their geographic distribution in the US. Results Using High Throughput Sequencing (HTS) we obtained high-density molecular markers (i.e., SNPs) for TCA samples. With 26,657 SNPs we identified genetic variation among TCA populations in different states across the US (i.e., Texas, Louisiana, Alabama, Mississippi, Georgia, and Florida) and in South America (i.e., Argentina, Colombia, and Peru). Conclusion Our results underscore that for recently introduced invasive species, increasing the number of molecular markers used in population genetic studies can provide greater resolution. High-resolution information on regional genetic differences can help inform pest management strategies.