Stingless bees are important pollinators for various plant crops. We investigated the susceptibility of Tetragonisca fiebrigi to sublethal concentrations of insecticides fipronil, malathion, and thiamethoxam (administered through contact and ingestion) by determining the LC50 values after 24 hours of exposure and analyzing changes in the activity of esterase isoenzymes and the chromatin in brain cells. The LC50...