Phylogenetic relationships, species limits, and host specificity of gall-forming Fergusonina flies (Diptera : Fergusoninidae) feeding on Melaleuca (Myrtaceae)

Abstract

Phylogenetic analysis of recently described gall-forming Fergusonina Malloch flies was performed using DNA sequence data from the mitochondrial cytochrome oxidase I gene. Fifty-three flies reared from nine species of Melaleuca L. were sequenced. Species boundaries delimited by mitochondrial data confirm recent morphological investigation with one exception. Fergusonina turneri Taylor, believed to feed on both Melaleuca quinquenervia (Cav.) S. T. Blake and Melaleuca fluviatilis Barlow, seems to be comprised of two cryptic species, each specialized on one of the two hosts. Because F. turneri is under consideration as a potential biological control agent for invasive M. quinquenervia in the Florida Everglades, understanding cryptic variation and the degree of dietary specialization of this species is critical.