Results of catches by sticky traps to detect honey bee parasitoids in Piedmont (Italy)

Apis mellifera parasitoid attack has proved to be more widespread and significant than previously thought, related to newly-discovered roles played by Phoridae family species. Not only has bee decline in North America and Apocephalus borealis (Core et al, 2012) been linked, but also facultative parasitoid Megaselia rufipes has been detected on honeybees with deformed wings (Dutto and Ferrazzi, 2014) in the Italian northwest (Piedmont). Senotainia tricuspis, the primary honeybee parasitoid in southern and Central Europe and north Africa studied since 1949 (Simintzis, 1949) and known to cause particular harm in central and southern Italy, is now considered associated with honeybee die-offs in many areas. In fact, reports by some beekeepers using sticky traps to catch this dipteron have suggested the species has a widespread presence. To assess the true incidence of this and other parasitoids, sticky traps were deployed in four rural Cuneo province municipalities (Piedmont). Specifically, white, yellow, and grey traps were placed in the roof fronts of hives located in different environments (near a river, a wood, a kiwifruit orchard, and grazing lands). Traps caught species belonging to the Calliphoridae, Sarcophagidae and Tachinidae, Panorpa, Phoridae, Tabanidae, and Aphididae taxa. The principal species caught were honeybees, with a significant difference compared to other taxa. Significant differences have been found also in the catches with adhesive strips of different colours. S. tricuspis was undetected, implying its absence in the wide area sampled. However, caution is advised when interpreting reports, as this species can be confused with other Sarcophagidae.