Stealing behaviour is well-documented in spider, potter, digger and sphecid wasps (see Field 1992 for review). The wasp's supplies are generally paralysed insects and spiders. In a typical scenario, a large piece of food is left on the ground by the owner when inspecting a nest or a possible way and direction for subsequent transport. Fights over the ownership of the disputed prey are commonly observed. Field (1992) distinguishes the theft of provisions from outside a nest from the theft of provisions left inside a nest. He suggests that theft outside nests does not occur in bees, but Thorp & Briggs (1980) observed Apis mellifera Linnaeus when stealing pollen from the legs of solitary bees. Thefts from inside nests were documented in Xylocopa pubescens Spinola (Mordechai et al. 1978) and possibly also in Eufriesea surinamensis Linnaeus (Myers & Loveless 1976). The most specialised inside nest theft strategy occur in eusocial species. They are specialised (sometimes obligatory) thieves called robbers. This behaviour is known in Apini, Bombini and Meliponini (Michener 1974). Lestrimelitta Friese and Cleptotrigona Moure (Meliponini) are genera consisting of eusocial obligate robber bees. Except eusocial bees, the theft of provisions seems to be rather ineffective and thus uncommon behaviour in bees, unlike in wasps, where the stolen provision is the prey.