Dioryctria merkeli, the loblolly pine coneworm moth, is a species of snout moth in the genus Dioryctria. It was described by Mutuura and Munroe, in 1979, and is found in the eastern United States, including Maryland, Texas, Mississippi, Georgia and Florida. The larvae feed on Pinus species. They bore into the cambium of the trunk, branches, and twigs of their host plant.