Talavera, AdriánPalmada Flores, MarcBurriel Carranza, BernatValbuena Ureña, EmilioMochales Riaño, GabrielAdams, DeanTejero Cicuéndez, HectorSoler Membrives, AnnaAmat, FèlixGuinart, DanielCarbonell, FrancescObon, ElenaMarquès Bonet, TomàsCarranza, Salvador2025-05-262025-05-262024-01-19Talavera, A., Palmada-Flores, M., Burriel-Carranza, B., Valbuena-Ureña, E., Mochales-Riaño, G., Adams, D. C., Tejero-Cicuéndez, H., Soler-Membrives, A., Amat, F., Guinart, D., Carbonell, F., Obon, E., Marquès-Bonet, T., & Carranza, S. (2024). Genomic insights into the Montseny brook newt (Calotriton arnoldi), a Critically Endangered glacial relict. iScience, 27(1). https://doi.org/10.1016/J.ISCI.2023.1086652589-004210.1016/j.isci.2023.108665https://hdl.handle.net/20.500.14352/120469AT is supported by “la Caixa” doctoral fellowship programme (LCF/BQ/DR20/11790007). MP-F is supported by “la Caixa” doctoral fellowship programme (LCF/BQ/DR20/11790032). BB-C was funded by FPU grant from Ministerio de Ciencia, Innovación y Universidades, Spain (FPU18/04742). GM-R was funded by an FPI grant from the Ministerio de Ciencia, Innovación y Universidades, Spain (PRE2019-088729). HT-C is supported by a Juan de la Cierva – Formación postdoctoral fellowship (FJC2021-046832-I) funded by MCIN/AEI/10.13039/501100011033 and by the European Union NextGenerationEU/PRTR. The work was funded by the grants PGC2018-098290-B-I00 (MCIU/AEI/FEDER, UE), Spain, and PID2021-128901NB-I00 (MCIN/AEI/10.13039/501100011033 and by ERDF, A way of making Europe), Spain to SC.The Montseny brook newt (Calotriton arnoldi), considered the most endangered amphibian in Europe, is a relict salamandrid species endemic to a small massif located in northeastern Spain. Although conservation efforts should always be guided by genomic studies, those are yet scarce among urodeles, hampered by the extreme sizes of their genomes. Here, we present the third available genome assembly for the order Caudata, and the first genomic study of the species and its sister taxon, the Pyrenean brook newt (Calotriton asper), combining whole-genome and ddRADseq data. Our results reveal significant demographic oscillations which accurately mirrored Europe’s climatic history. Although severe bottlenecks have led to depauperate genomic diversity and long runs of homozygosity along a gigantic genome, inbreeding might have been avoided by assortative mating strategies. Other life history traits, however, seem to have been less advantageous, and the lack of land dispersal has driven to exceptional levels of population fragmentation.engAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/journal articlehttps://doi.org/10.1016/j.isci.2023.108665https://www.sciencedirect.com/science/article/pii/S2589004223027426?via%3Dihubopen access597.6575.113591.5591.5GenomicsZoologyEcologyZoologíaAnfibiosGenéticaEcología (Biología)2401 Biología Animal (Zoología)2401.08 Genética Animal2401.06 Ecología Animal