A Way Through the Trees: Molecular Phylogenies Consistently Recover Two Clades of Aedes Mosquitoes

Phylogenetic analyses of molecular data have been critical in resolving deep and shallow relationships across the tree of life. Such analyses have provided clarity where traditional morphological analyses may not have, and have been instrumental in a range of evolutionary, systematic, and taxonomic studies for providing clarity to evolutionary relationships. One such case where evolutionary relationships are poorly understood is in the mosquito genus Aedes. Although this medically important genus of insects has received significant study, the majority of research has focused on those relatively few species that are invasive and transmit pathogens which cause disease. As a result, evolutionary relationships between Aedes mosquitoes are poorly understood, and the classification of the genus has been contentious, with numerous taxonomic changes over the last two decades being undertaken and reversed based entirely on analyses of somewhat limited morphological data. As a result, we conducted a literature review of molecular phylogenies and evaluated classificatory hypotheses under a framework based on observations of frequently occurring relationships among mosquito genera and subgenera. We found that molecular phylogenies consistently reflect two distinct clades of Aedes mosquitoes, each with other Aedini genera within them. We discuss these results in the context of ongoing debates over Aedes nomenclature. Our review demonstrates the ability for molecular phylogenies to aid in resolving long-standing debates on nomenclature.