Wastewater as a driver of lineage replacement in Parisotoma notabilis sensu lato (Collembola): L2 conquers the tundra, L1 dominates the taiga.

Wastewater is a widespread stressor, but its impact on the genetic structure of soil invertebrates remains poorly understood. We studied the distribution of genetic lineages of the parthenogenetic springtail Parisotoma notabilis sensu lato in tundra and taiga zones of the European North of Russia, focusing on wastewater-affected (technogenic) sites. Using COI and 28S rDNA markers, we analysed 90 specimens from 18 sites representing three habitat types (zonal, floodplain, technogenic) per zone and identified four lineages: L1, L2, L4 and L-East. Distribution was highly habitat-specific and primarily driven by both soil temperature and disturbance. In the tundra, L-East dominated natural sites but was absent from technogenic sites, where L2 predominated. In the taiga, technogenic sites were dominated by synanthropic L1, whereas L2 prevailed in natural forests and floodplains. Wastewater appears to act as a selective filter, reducing genetic diversity and being associated with zone-dependent lineage replacement: L2 replaces L-East in the tundra, while L1 dominates in the taiga. This temperature-associated pattern highlights the need for region-specific bioindication frameworks.