Biology subjects

Bilat, J.

Publications and source records attributed to Bilat, J..

4 recordsLinked to original sources

bioRxiv2026

Cryptic diversification proceeds despite historical and contemporary hybridization in Patagonian ants

Understanding how independently evolving lineages arise despite ongoing gene flow remains a central question in evolutionary biology. Although genomic studies increasingly suggest that hybridization can accompany diversification, empirical evidence from ecologically dominant insect groups remains limited. Here, we present the first population-scale phylogenomic analysis of Patagonian ants, sampling Dorymyrmex across approximately 450,000 km2. Using genome-wide SNPs, coalescent phylogenetics, phylogenetic networks, demographic modelling, species delimitation, and genome scans, we reconstruct the evolutionary history of this widespread genus. We discovered extensive cryptic diversity with strong genomic differentiation and detected both recent and historical hybridization, demonstrating that substantial genomic divergence accumulated despite recurrent gene flow events. Genome scans further identify candidate loci associated with adaptation to Patagonias contrasting environments, suggesting that ecological divergence contributed to lineage diversification. Our results show that cryptic diversification can proceed despite recurrent gene flow, supporting hybridization as an integral component of the diversification process. More broadly, this study illustrates how genome-scale data can reveal hidden biodiversity and the evolutionary processes shaping it in ecologically important but genomically understudied taxa.

evolutionary biology↗

bioRxiv2025

The role of peripheral regions in shaping the phylogeography of the Bear s ear complex across the Alps

AimPeripheral regions of the Alps are often overlooked in molecular studies, yet they may play a major role in shaping the current distribution of species and genetic lineages. LocationEurope TaxonAngiosperms (Primulaceae: Primula) MethodsBy focusing on the bears ear (Primula auricula) complex as model species, we used genetic inferences for population genetic structure and performed genetic reconstructions, species delimitations and divergence time estimates in order to get a detailed view of its molecular evolution and current genetic structuring across the Alps sensu lato. ResultsThe Lombardian Alps and the southern eastern Alps are genetically distinct in the vicinity of the Adige valley. The northern and western Alps and their peripheries constitute a third clade and are separated by the siliceous central Alps. Within the latter, an additional cluster made of singular populations from the Devoluy and Vercors regions is retrieved, likely reflecting a strong founder effect rather than an ancient divergence. Main conclusionsThe biogeographic history P. auricula sensu lato pinpoints the importance of the peripheral regions in a phylogeographic context. Populations from northern peripheral regions exhibit long-lasting isolation and in situ survival during glaciations, followed by recolonization into the central Alpine massif.

genetics↗

bioRxiv2025

Conservation strategy insights for three protected Phengaris butterflies combining genetic and landscape analyses

Biodiversity loss is accelerating globally, with insects among the most affected taxa. Wetlands, crucial ecosystems providing essential services, have experienced significant decline due to agricultural intensification and habitat destruction. These changes threaten species that rely on wetland habitats, such as the Phengaris butterflies, which exhibit complex ecological dependencies on specific host plants and ant species. Their populations are structured into metapopulations, where connectivity between habitat patches plays a crucial role in species persistence. This study focuses on population genomics and landscape analysis of three Phengaris species (P. alcon, P. nausithous, P. teleius) in the Bugey Mountain Massif, France, with the aim of developing a conservation strategy. Using ddRAD sequencing, we analyzed genetic diversity, population structure, and gene flow across multiple localities, revealing distinct population clusters with varying degrees of connectivity. Despite some populations exhibiting high genetic diversity levels, others demonstrate low heterozygosity and signs of genetic isolation, emphasizing conservation concerns. Migration estimates and resistance mapping further identified key dispersal corridors and isolated patches requiring targeted interventions. Our findings support metapopulation conservation strategies that prioritize maintaining connectivity, enhancing degraded patches, and identifying new potential habitats. By combining genomic and landscape data, we propose an evidence-based approach to conservation planning, facilitating adaptive management for Phengaris species. This study provides a practical framework for habitat restoration and corridor management in fragmented ecosystems, ensuring long-term species resilience in rapidly changing landscapes.

evolutionary biology↗

bioRxiv2022

The identity of Argyria lacteella (Fabricius, 1794) (Lepidoptera, Pyraloidea, Crambinae), synonyms, and related species using morphology and DNA capture in type specimens

Recent developments in museomics enable genetic information to be recovered from previously unusable collection specimens and thus to answer complex taxonomic questions. Here we apply museomics to a taxonomic problem involving several species of Argyria Hubner (Pyraloidea, Crambinae), with previously unrecognized morphological variation. By analysing the DNA barcode (COI-5P) in numerous specimens, we aimed to reconstruct phylogenetic relationships between species, to provide better evidence for synonymies, and to circumscribe their geographical distribution. Using an innovative DNA hybridization capture protocol, we partially recovered the DNA barcode of the lectotype of Argyria lacteella (Fabricius, 1794) for comparison with the 229 DNA barcode sequences of Argyria specimens available in the Barcode of Life Datasystems, and this firmly establishes the identity of the species. The same protocol was used for the following type specimens: the Argyria abronalis (Walker, 1859) holotype, thus confirming the synonymy of this name with A. lacteella, the holotype of A. lusella (Zeller, 1863), rev. syn., the holotype of A. multifacta Dyar, 1914, syn. n., newly synonymized with A. lacteella, and a specimen of Argyria diplomochalis Dyar, 1913, collected in 1992. A complementary sampling composed of nine specimens of A. lacteella, A. diplomochalis, A. centrifugens Dyar, 1914 and A. gonogramma Dyar, 1915, from North to South America, were integrated using classical COI amplification and Sanger sequencing. Argyria gonogramma Dyar, described from Bermuda, is the name to be applied to the more widespread North American species formerly identified as A. lacteella. Following morphological study of its holotype, Argyria vestalis Butler, 1878, syn. n. is also synonymized with A. lacteella. The name A. pusillalis Hubner, 1818, is considered a nomen dubium associated with A. gonogramma. The adult morphology is diagnosed and illustrated, and distributions are plotted for A. lacteella, A. diplomochalis, A. centrifugens, and A. gonogramma based on slightly more than 800 specimens. For the first time, DNA barcode sequences are provided for the Antillean A. diplomochalis. Our work highlights the efficiency of the DNA hybrid capture enrichment method to retrieve DNA barcodes from 18th and 19th century type specimens in order to solve taxonomic issues in Lepidoptera.

zoology↗