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Bembicinae = Link 1
Species of the subfamily Bembicinae construct their nests in the soil, storing them with adult flies, such as Syrphidae and Tabanidae. A few species are known to prey on Orthoptera, and there are records of other insect groups serving as food for Bembex broods (Wheeler & Down 1933). An African species of Bembex was found to attack lycaenid butterflies, and another Bembex sp. in Australia captures adult damselflies for its brood. The latter was presumed to be a temporary measure made necessary by the absence of the normal food insects. Larvae are fed freshly killed prey throughout their development.
Bembex tarsata Panz. of Europe serves as a representative example for the subfamily. The female pounces on her prey aburptly, and the battle that ensues usually results in the death of the latter through repeated and wholesale stinging (Fabre 1879). The prey is then carried by flight to the nest. Maternal care and feeding continue during the two weeks required for the larva to attain maturity; and the number of flies provided for each larva is dependent on its size.
In the Bembicinae, eggs are laid in the cells and provisions are usually brought in only after the larva has hatched, although some species are known to place the egg on a single prey in the bottom of the cell. Females may tend a number of brood larvae.