A multigene phylogeny of the fly superfamily Asiloidea (Insecta): Taxon sampling and additional genes reveal the sister-group to all higher flies (Cyclorrhapha)

Abstract

Asiloidea are a group of 9 lower brachyceran fly families, considered to be the closest relative to the large Metazoan radiation Eremoneura (Cyclorrhapha+Empidoidea). The evidence for asiloid monophyly is limited, and few characters define the relationships between the families of Asiloidea and Eremoneura. Additionally, enigmatic genera, Hilarimorpha and Apystomyia, retain morphological characters of both asiloids and higher flies. We use the nuclear protein-coding gene CAD and 28S rDNA to test the monophyly of Asiloidea and to resolve its relationship to Eremoneura. We explore the effects of taxon sampling on support values and topological stability, the resolving power of additional genes, and hypothesis testing using four-cluster likelihood mapping. We find that: (1) the 'asiloid' genus Apystomyia is sister to Cyclorrhapha, (2) the remaining asiloids are monophyletic at the exclusion of the family Bombyliidae, and (3) our best estimate of relationships places the asiloid flies excluding Bombyliidae as the sister-group to Eremoneura, though high support is lacking.