Population structure, adaptation and divergence of the meadow spittlebug, <i>Philaenus spumarius</i> (Hemiptera, Aphrophoridae), revealed by genomic and morphological data

Understanding patterns of population differentiation and gene flow in insect vectors plant diseases is crucial for the implementation management programs disease. We investigated morphological genome-wide variation across distribution range spittlebug Philaenus spumarius (Linnaeus, 1758) (Hemiptera, Auchenorrhyncha, Aphrophoridae), presently most important vector pathogenic bacterium Xylella fastidiosa Wells et al., 1987 Europe. found divergence between P. a very closely related species, tesselatus Melichar, 1899, at RAD sequencing markers. The two species may be identified by morphology male genitalia but are not differentiated mitochondrial COI, making DNA barcoding with this ineffective. This highlights importance using integrative approaches taxonomy. detected admixture from Morocco Iberian Peninsula, suggesting gene-flow them. Within , we pattern isolation-by-distance European populations, likely acting alongside other factors restricting flow. Varying levels co-occurrence different lineages, showing heterogeneous admixture, suggest isolation mechanisms. transatlantic populations North America Azores were genetically closer to British analyzed here, an origin North-Western Europe, as already DNA. Nevertheless, these have been produced through colonization events. SNPs signatures positive selection associated environmental variables, especially extremes temperature precipitation. genomics approach provided new insights into divergence, adaptation spittlebugs led several hypotheses that require further local investigation.