Gaytán, ÁlvaroBergsten, JohannesCanelo, TaraPérez Izquierdo, CarlosSantoro, MaríaBonal Andrés, Raúl2026-02-242026-02-242020-09Gaytán Á, Bergsten J, Canelo T, Pérez‐Izquierdo C, Santoro M, Bonal R. DNA Barcoding and geographical scale effect: The problems of undersampling genetic diversity hotspots. Ecology and Evolution 2020;10:10754–72. https://doi.org/10.1002/ece3.6733.10.1002/ece3.6733https://hdl.handle.net/20.500.14352/133115Acknowledgements: RB was supported by a contract of the Atracción de Talento Investigador Programme (Gobierno de Extremadura TA13032). This work was financed by the projects PPII-2014-01-P from Junta de Comunidades de Castilla-La Mancha/European Social Fund and AGL2014-54739-R from Spanish Ministry of Economy and Competitiveness and the European Social Fund.DNA barcoding identification needs a good characterization of intraspecific genetic divergence to establish the limits between species. Yet, the number of barcodes per species is many times low and geographically restricted. A poor coverage of the species distribution range may hamper identification, especially when undersampled areas host genetically distinct lineages. If so, the genetic distance between some query sequences and reference barcodes may exceed the maximum intraspecific threshold for unequivocal species assignation. Taking a group of herbivores (moths) in Europe as model system, we found that the number of DNA barcodes from southern Europe is proportionally very low in the Barcoding of Life Data Systems. This geographical bias complicates the identification of southern query sequences, due to their high intraspecific genetic distance with respect to barcodes from higher latitudes. Pairwise intraspecific genetic divergence increased along with spatial distance, but was higher when at least one of the sampling sites was in southern Europe. Accordingly, GMYC (General Mixed Yule Coalescent) single-threshold model retrieved clusters constituted exclusively by Iberian haplotypes, some of which could correspond to cryptic species. The number of putative species retrieved was more reliable than that of multiple-threshold GMYC but very similar to results from ABGD and jMOTU. Our results support GMYC as a key resource for species delimitation within poorly inventoried biogeographic regions in Europe, where historical factors (e.g., glaciations) have promoted genetic diversity and singularity. Future European DNA barcoding initiatives should be preferentially performed along latitudinal gradients, with special focus on southern peninsulas.engAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/journal article2045-7758https://doi.org/10.1002/ece3.6733https://onlinelibrary.wiley.com/doi/10.1002/ece3.6733open access575575.8577.21595.7Cytochrome c oxidase subunit IGlacial refugiaIntraspecific genetic divergenceLepidopteraGenéticaEvoluciónBiología molecular (Biología)Insectos2401.08 Genética Animal2415 Biología Molecular2413 Biología de Insectos (Entomología)