Patterns of Speciation in a parapatric pair of Saturnia moths as revealed by Target Capture
Résumé
The focus of this study was to understand the evolutionary relationships and taxonomy of widely
distributed parapatric pair of Saturnia pavonia and Saturnia pavoniella (Lepidoptera: Saturniidae)
in Europe. To address species delimitation challenges associated with many parapatric taxa,
target enrichment and mtDNA sequencing was employed alongside analyses of admixture, gene
flow, hybridization, and introgression. The dataset included individuals from both species as well
as two hybrids from and broadly outside the contact zone. Nuclear markers strongly supported
both S. pavonia and S. pavoniella as two distinct species, with the hybrids grouping together
as intermediate and separate from both species. However, the maximum likelihood (ML) tree
generated from mtDNA sequencing data presented a different picture, showing both taxa to be
phylogenetically intermixed. This inconsistency may be attributed to mitonuclear discordance,
which can arise from biological factors (e.g., introgressive hybridization or incomplete lineage
sorting) or operational factors (e.g., misidentification or incorrect species delimitation). We further
discuss our results from evolutionary point of view taking into consideration the past climatic
oscillations that has likely shaped the present dynamics between the species. Overall, this study
demonstrated the effectiveness of the target enrichment approach in resolving the phylogenetic
relationships and providing insights into the taxonomic and phylogenetic relationships between
these species.