Deformed wings in introduced solitary bees, Megachile spp., independent of virus infections

Insect wing deformities can be caused by various factors, including the Deformed wing virus (DWV). Symptomatic and asymptomatic specimens of the introduced solitary wild bees Megachile sculpturalis and Megachile disjunctiformis collected at eleven Central European locations were screened for DWV infections. Even though virus spillover is common, and DWV was detected in other bee species collected in the same habitat as Megachile spp., neither DWV-A nor DWV-B were found in any of the samples (N = 54) including two symptomatic males with deformed wings. This indicates that other stressors were responsible for the observed clinical symptoms, thereby highlighting the necessity of differential diagnostics.