Hornet venoms: lethalities and lethal capacities.

The i.v. LD50 values to mice of pure venoms of Vespa mandarinia japonica, V. simillima xanthoptera, V. tropica deusta and V. l. luctuosa were, respectively, 4.1, 3.1, 2.8 and 1.6 mg/kg. The LD50 value of 1.6 mg/kg distinguishes the venom of V. luctuosa as the most lethal known wasp venom. To measure the absolute lethality of a single sting, a new index, called lethal capacity, based on the amount of venom possessed by an individual and its lethality is presented. V. mandarinia and V. tropica are the most venomous known insects, with a lethal capacity of one sting from V. mandarinia delivering an LD50 (i.v.) dosage of venom to 270 g of mouse. The lethal capacity for an entire hornet colony, called colony lethal capacity, for V. tropica is 84 kg of mouse/colony.