Population genetics and the role of dispersal barriers in the Antarctic springtail <i>Kaylathalia klovstadi</i> (Collembola, Isotomidae)

Abstract Isolation and extreme environmental conditions have significantly impacted terrestrial invertebrate biodiversity in Antarctica, with glacial cycles further limiting animal diversity to a small number of species. Among these, springtails are relatively abundant, though their taxonomic diversity remains low. Antarctic glaciers may serve as major dispersal barriers, leading to high levels of genetic divergence among isolated populations. In Victoria Land (continental Antarctica), the Tucker Glacier has been proposed as an example of such a barrier; however, different species or taxa may respond differently to the same geographical features. In this study, we tested whether geographic distance, major glacier tongues, and seawater channels influence the distribution of Kaylathalia klovstadi (Collembola; Isotomidae) in Northern Victoria Land. We conducted mitochondrial DNA haplotype analysis on fragments of cytochrome c oxidase subunit 1 ( cox1 ) and ATP synthase 6 ( atp6 ) in 62 individuals from six K. klovstadi populations. Our analysis provides new insights into the genetic diversity and distribution patterns of K. klovstadi by incorporating additional sampling sites, specimens, and molecular markers. We challenge previous views regarding the role of the Tucker Glacier as a significant physical barrier to springtail dispersal in Northern Victoria Land. Our findings suggest that the impact of physical barriers on the genetic diversity of Antarctic Collembola, including the species studied here, requires a more careful evaluation.