NOTES ON NESTING AND GREGARIOUS BEHAVIOR OF A BLUE NEST-RENTING WASP, CHALYBION JAPONICUM (GRIBODO) WITH COMMENTS ON COMMONLY USED NAME FOR CHALYBION SPECIES (HYMENOPTERA: SPHECIDAE)

Abstract Notes on nesting and gregarious behavior of the blue nest renting wasp Chalybion japonicum (Gribodo) are presented. Three focal nests, freshly attached to the walls of an abandoned house belonging to the mud dauber wasp Sceliphron madraspatanum were occupied by C. japonicum, suggesting that the wasp is a nest invader of S. madraspatanum. Aggregation of C. japonicum males on the string of the sack, which hung loosely beneath the ceiling, undoubtedly plays a role to help males finding females easily rather than by having to take flight. Discussion on relationship of occurrence between C. japonicum and C. bengalense is included. The new appellation “nest renting wasps” for Chalybion species is suggested.