Genomes of Ganaspis near brasiliensis (Hymenoptera: Figitidae)

During the last decade, the spotted-wing drosophila, Drosophila suzukii, has spread from eastern Asia to the Americas, Europe, and Africa. This fly attacks many species of cultivated and wild fruits with soft, thin skins, where its serrated ovipositor allows it to lay eggs in undamaged fruit. Parasitoids from the native range of D. suzukii may provide sustainable management of this highly mobile, polyphagous pest by controlling fly populations at the landscape level. Among these parasitoids, host-specificity testing has revealed a lineage of Ganaspis near brasiliensis more host-specific to D. suzukii than other species. This lineage appears to be a cryptic species near G. brasiliensis. Here we present results on divergence in genomic sequences and reproductive isolation between cryptic species of Ganaspis near brasiliensis. We studied five populations, two from China, two from Japan, and one from Canada, identified as the G1 versus G3 lineages based on differences in COI sequences. We assembled and annotated the genomes of these populations, and analyzed sequence divergence between them. Finally, we report results from crosses to test reproductive compatibility between the G3 lineage from China and the G1 lineage from Japan. The combined evidence of differences in the assemblies and annotations of the G1 and G3 lineages and their reproductive incompatibility shows that they are different species, and that the previous decision to evaluate the lineages separately, and only import and introduce the more specific lineage to North America and Europe, was appropriate.