De Sosa Carrasco, IreneFernández Marchán, DanielNovo Rodríguez, MartaAlmodóvar Pérez, Ana MaríaDíaz Cosín, Darío2025-01-132025-01-132022-10De Sosa I, Marchán DF, Novo M, Almodóvar A, Díaz Cosín DJ. Phylogeography of a riparian earthworm shows environmental factors influence genetic structure. Journal of Biogeography 2023;50:156–68. https://doi.org/10.1111/jbi.14518.0305-027010.1111/jbi.14518https://hdl.handle.net/20.500.14352/114089Acknowledgements: IS was supported by a Predoctoral Fellowship grant from Universidad Complutense de Madrid, Spain. DF was supported by a Juan de la Cierva Formación grant from the Spanish Government (FJCI-2017-32895) and a MOPGA grant from the Ministry for Europe and Foreign Affairs, in collaboration with the Ministry for Higher Education and Research (mopga-postdoc-3--6111272103). MN was supported by a Ramón y Cajal Fellowship (RYC2018-024654-I) from MCIN/AEI/10.13039/501100011033 and “ESF: Investing in your future.” This research was funded by project CGL2013-42908-P from the Spanish Government, by Grant PGC2018-094112-A-100 from MCIN/AEI/10.13039/501100011033, and by “ERDF: A way of making Europe.” No permits were needed for this work.Aim The study of cosmopolitan earthworms could be even more interesting than that of endemic species in revealing evolutionary processes. Previous research on the cosmopolitan wormEiseniella tetraedrahas indicated some phylogeographic structure among populations, but the factors responsible remain unresolved. We hypothesized that environmental factors and dispersal have shaped the distribution of the species' lineages. Location Spain and Portugal; Iberian Peninsula. Taxon Eiseniella tetraedra(Lumbricidae, Oligochaeta, Annelida). Methods We collected 739 specimens ofEiseniella tetraedrafrom 65 localities around the Iberian Peninsula between 2012 and 2016. We performed phylogenetic analysis (Bayesian Inference and maximum likelihood) using two mitochondrial (COI and 16S) and one nuclear marker (28S). Furthermore, we studied their genetic diversity and historic demography based on the COI gene. Correlations between genetic diversity and 22 environmental factors were tested. Results Eiseniella tetraedrashowed high diversity in the Iberian Peninsula, with eight different lineages nested in two clades. We found lineages mostly restricted to the northern region, while others were distributed throughout the Iberian Peninsula. Habitat stability, that is, constant availability or lack of water, also correlated with genetic diversity. Thus, although no clear phylogeographic pattern was found, environmental factors (such as precipitation, temperature, and soil pH) and habitat stability influenced the distribution of genetic variability. Main Conclusions Eiseniella tetraedrais an earthworm with great genetic variability. We show that the ranges of species with high relative dispersal ability and ambiguous phylogeographic patterns may be better explained by influence of environmental conditions rather than specific geographic features. Adaptation to unstable conditions has been shown to confer more success on one of the two major genetic clades recovered, pointing to ecological plasticity as a key for evolutionary success.engAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/journal article1365-2699https://doi.org/10.1111/jbi.14518open access591.1595.14575.86574.9AnnelidaDispersionEcological diversityEiseniella tetraedraGenetic variabilitySemi-aquatic habitatEcología (Biología)InvertebradosEvolución2401.06 Ecología Animal2401.17 Invertebrados