Shallow Whole-Genome Sequencing of <i>Aedes japonicus</i> and <i>Aedes koreicus</i> from Italy and an Updated Picture of Their Evolution Based on Mitogenomics and Barcoding.

<i>Aedes japonicus</i> and <i>Aedes koreicus</i> are two invasive mosquitoes native to East Asia that are quickly establishing in temperate regions of Europe. Both species are vectors of arboviruses, but we currently lack a clear understanding of their evolution. Here, we present new short-read, shallow genome sequencing of <i>A. japonicus</i> and <i>A. koreicus</i> individuals from northern Italy, which we used for downstream phylogenetic and barcode analyses. We explored associated microbial DNA and found high occurrences of <i>Delftia</i> bacteria in both samples, but neither <i>Asaia</i> nor <i>Wolbachia.</i> We then assembled complete mitogenomes and used these data to infer divergence times estimating the split of <i>A. japonicus</i> from <i>A. koreicus</i> in the Oligocene, which was more recent than that previously reported using mitochondrial markers. We recover a younger age for most other nodes within Aedini and other Culicidae. COI barcoding and phylogenetic analyses indicate that <i>A. japonicus yaeyamensis</i>, <i>A. japonicus amamiensis</i>, and the two <i>A. koreicus</i> sampled from Europe should be considered as separate species within a monophyletic species complex. Our studies further clarify the evolution of <i>A. japonicus</i> and <i>A. koreicus,</i> and indicate the need to obtain whole-genome data from putative species in order to disentangle their complex patterns of evolution.