Sting embedment and avulsion in yellowjackets (Hymenoptera: Vespidae): A functional equivalent to autotomy

Clinical studies, laboratory tests, and field observations confirm that the barbed sting of a yellowjacket wasp, Vespula maculifrons (Buysson), often becomes firmly anchored in human skin. Although the wasp cannot pull away from (i.e. autotomize) its sting when this occurs, if the insect is forcibly removed by the victim, the sting apparatus tends to be more readily torn from its abdomen than are the embedded lancets torn from the victim's skin. Associated with the release of alarm pheromone and prolonged injection of venom, this mechanism of sting loss by victim-mediated avulsion appears to be functionally equivalent to true autotomy in other social Hymenoptera. A second yellowjacket species, V. germanica (F.), exhibited the same type of sting loss, but at considerably lower frequencies.