The evolutionary history of capital-breeding moths through the lens of wild silkmoths (Saturniidae) phylogenomics

International audienceWild silkmoths (Saturniidae) are large capital-breeding insects with non-feeding adults that have short lifespan entirely devoted to reproduction. They exhibit a dazzling diversity of sizes, forms, and life-histories inviting questions about the role that key traits may have played in spurring out species diversification and biogeographical movements in organisms with such extreme reproductive strategy. Yet, the absence of a robust phylogenetic framework based on comprehensive taxonomic sampling impedes our understanding of their evolutionary history. We analyzed 1,024 ultraconserved elements (UCEs) and their flanking regions to infer the relationships among 338 species of Saturniidae representing all subfamilies, tribes, and genera. We performed dating and historical biogeographic analyses to reconstruct their evolutionary history in space and time. Rather unexpectedly for a taxonomically well-known family such as Saturniidae, the alignment of taxonomic divisions and ranks with our phylogenetic results led us to propose substantial rearrangements of the family classification. Saturniids most likely originated in the Neotropics, shortly after the Cretaceous-Paleogene extinction event (ca 64.0-52.0 Ma). Old World lineages stemmed from two independent colonization events during the Eocene, presumably through the Bering-Land-Bridge. Extant subfamilies showed limited mobility across biogeographical regions, except for Saturniinae, a subfamily now present on all continents but Antarctica. These results provide a framework for the integration of saturniid evolutionary history into further global studies of biodiversity and conservation, as well as for in-depth investigations of the spatial and temporal dynamics in all lineages and of the role that key innovations played in driving species diversification of these capital-breeding moths