Research Entomologist Smithsonian Institution Washington, District of Columbia
Assassin flies (Diptera: Asilidae) are a diverse family that plays an essential ecological role as top aerial and venomous predators. Little is known about the evolution of their predatory habits. This study provides a novel phylogenetic hypothesis of Asilidae along with prey preference and ancestral state reconstruction in a maximum likelihood framework. This study is based on 176 assassin fly species, 35 Asiloidea outgroup species, prey preference data accumulated from literature and museum collections, and approximately 7,913 bp of nuclear DNA from five genes (18S and 28S rDNA, AATS, CAD, and EF-1a protein-encoding DNA) and mitochondrial DNA from one gene (COI). Of the 12 asilid subfamilies included in the analysis the monophyly of six was supported. We used ancestral state reconstruction and stochastic character mapping to test whether a polyphagous arthropod predator is the ancestral state for Asilidae. Assassin flies are polyphagous arthropod predators, with specialized arthropod prey preferences evolving 20 independent times across the Asilidae phylogeny.