GENERIC REVISION OF PHORIDAE OF THE NEARCTIC REGION AND PHYLOGENETIC CLASSIFICATION OF PHORIDAE, SCIADOCERIDAE, AND IRONOMYIIDAE (DIPTERA: PHORIDEA)

Abstract The Nearctic Region genera of Phoridae are revised, and it is shown that the current classification into three subfamilies is inadequate. The hypothesis that the most closely related taxa to the Phoridae are the Sciadoceridae and Ironomyiidae is supported. Use of these outgroups to polarize character states in the Phoridae allows the reorganization of this family into five subfamilies: Hypocerinae, Phorinae, Aenigmatiinae, Conicerinae, and Metopininae. The newly re-defined Phorinae is the adelphotaxon (sister-group) of the Aenigmatiinae + Conicerinae + Metopininae, among which the relationships are unresolved. The hypocerines are the adelphotaxon of all other extant Phoridae. Within the Hypocerinae the relationships of the 15 included world genera are hypothesized, and three new genera are proposed. The relationships of the eight world phorine genera are only partly resolved. The Aenigmatiinae is organized into two tribes: Aenigmatiini and Diplonevrini. The relationships of the seven world genera of Diplonevrini are hypothesized, whereas those of the Aenigmatiini are not discussed. The six world conicerine genera are revised and their relationships hypothesized. In the Metopininae, two major groups are recognized, theMetopina-group and theMegaselia-group.BeckerinaMalloch is the adelphotaxon of these two groups, whereasRhopicaSchmitz andTriphlebaRondani are successive outgroups of all metopinines. TheMetopina-group is mostly tropical in distribution and is not discussed further. TheMegaselia-group is partially organized into theGymnophora-subgroup and theApocephalus-subgroup. Species-level revisions of genera are needed before further progress can be made in this family, because the distribution of character states is insufficiently known. Genera in great need of revision includePeromitraEnderlein,ChaetopleurophoraSchmitz,MegaseliaRondani, andApocephalusCoquillett.