Large pathogen screening reveals first report of Megaselia scalaris (Diptera: Phoridae) parasitizing Apis mellifera intermissa (Hymenoptera: Apidae).

As it is most likely that global warming will also lead to a shift in pollinator-habitats northwards, the study of southern species becomes more and more important. Pathogen screenings in subspecies of Apis mellifera capable of withstanding higher temperatures, provide an insight into future pathogen host interactions. Screenings in different climate regions also provide a global perspective on the prevalence of certain pathogens. In this project, we performed a pathogen screening in Apis mellifera intermissa, a native subspecies of Algeria in northern Africa. Colonies were sampled from different areas in the region of Annaba over a period of two years. Several pathogens were detected, among them Apicystis bombi, Crithidia mellificae, Nosema ceranae, Paenibacillus larvae, Lake Sinai Virus, Sacbrood Virus and Deformed Wing Virus (DWV). Our screening also revealed a phoroid fly, Megaselia scalaris, parasitizing honey bee colonies, which we report here for the first time. In addition, we found DWV to be present in the adult flies and replicating virus in the larval stages of the fly, which could indicate that M. scalaris acts as a vector of DWV.