A review of wing reduction and loss in the Sphaeroceridae and the evolution of winglessness in the Australian species of Howickia Richards (Diptera: Sphaeroceridae).

Abstract

Flightlessness in Diptera is discussed and incidence of wing reduction and loss in the Sphaeroceridae is reviewed. The genus Howickia Richards is particularly unique among genera which display flightlessness because it contains macropterous, brachypterous and apterous species, making it ideal for the study of the evolution of winglessness. This study illustrated, documented and phylogenetically analysed 26 Australian Howickia and Howickia-like species from the University of Guelph Insect Collection. COI data from sphaerocerids around the world as well as morphological data are used to determine outgroups for a morphology-based phylogenetic analysis. Results of the molecular analysis contentiously place Howickia within the strictly New World epandrial process group. Results of the morphological phylogenetic analysis establish one large clade and seven species groups. According to the phylogenetic analysis, wing loss has evolved independently at least three times in Australian Howickia. Several synonymies are suggested for consideration in a future revision.