Pollen Robbing Behaviors Observed in Two Species of Introduced Stingless Bees (Hymenoptera, Apidae)

Pollen robbing behaviors of two species of stingless bees, Trigona itama introduced from Indonesia and Nannotrigona testaceicornis from Brazil were observed on leguminous flowers, Lespedeza thunbergii, alfalfa and Chinese milk vetch. Foragers of both species made a hole at the anterior tip of the keel petal so as to steal pollen without tripping and reused these holes. This is the first authentic record of pollen robbing observed in leguminous plants.