First record of the pine sawfly Neodiprion warreni (Hymenoptera, Diprionidae) in the state of Tennessee and on Pinus virginiana

Pine sawflies in the genus Neodiprion Rohwer are widely distributed across the Northern Hemisphere and are pests of commercially important conifer trees. While sampling for Neodiprion species in eastern North America, two colonies of Neodiprion warreni Ross were discovered in Tennessee feeding on Pinus virginiana Mill. These are the first records of N. warreni in Tennessee and on the host P. virginiana. Here, we use a combination of larval and adult female morphology to confirm species identification. We also discuss two potential explanations for these observations: N. warreni was always present in Tennessee and feeding on P. virginiana but, until now, has gone unreported or these new records are attributable to a recent range expansion and host shift. We also discuss potential economic and evolutionary implications of range expansions and host shifts in plant-feeding insect pest species.