Leucopis spp. (Diptera: Chamaemyiidae) predators of hemlock woolly adelgid in the Pacific Northwest: Potential biological control agents in the eastern U.S.

Two species of Leucopis have been found to be abundant and frequent associates of hemlock woolly adelgid in the Pacific Northwest.  Current evidence suggests that these species are equally or more important to the population dynamics of the hemlock woolly adelgid in the Pacific Northwest than Laricobius nigrinus, a Pacific Northwest predator that has already been introduced in the eastern US for biological control.  The predators have been shown to prefer hemlock woolly adelgid to other native adlegid species in laboratory bioassays.  Genetic analyses of Leucopis found in eastern and western North America show genetically distinct geographical populations within species.  Introduction of these species to eastern North America has the potential to significantly improve biological control efforts.