A New Case of Honeybee Apis mellifera Infection with Bumblebee Parasite Apicystis bombi (Apicomplexa: Neogregarinorida)

The Apicystis bombi neogregarines parasitize bumblebees. Apis mellifera is its accidental host, but, in the future, it might become its ultimate host. Using polymerase chain reaction and microscopic analysis, we found A. bombi in 1 of 10 apiaries in Central Europe. The colony was queenless, with rebel workers. The parasite was detected in the hemolymph and digestive tracts but not in the fat bodies of the honeybee workers, whereas in its original host (bumblebees), it also occurs in the fat bodies.