Molecular markers reveal diversity in composition of (Hymenoptera: Megastigmidae) from eucalypt galls.

Since outbreaks of the invasive blue gum chalcids spp. began, the genus (Hymenoptera: Megastigmidae) has been increasingly studied as containing potential biocontrol agents against these pests. species have been collected and described from Australia, the presumed origin of spp., with and reported as spp. parasitoids established outside of Australia. Parasitic have been reported to occur locally in the Neotropics, Afrotropic, Palearctic, and Indomalaya biogeographic realms, and in many cases described as new to science. However, molecular tools have not been used in studying parasitic , and difficulties in morphological taxonomy have compromised further understanding of eucalypt-associated as well as the - association. In this study, we used molecular markers to study the species composition and phylogeny of collected from eucalypt galls in Australia and from spp. galls from South Africa, Kenya, Israel, China, and Vietnam. We record thirteen discrete species and a species complex associated with eucalypt galls. A summary of morphological characters is provided to assist morphological delimitation of the studied group. A phylogeny based on 28S rDNA identified species groups of importance to spp. biocontrol agents from four clades with nine species. Relationships between from eucalypt galls and their phytophagous congeners were unresolved. Further molecular work is needed to clarify the identity of many species.