The mycotoxin, F-2, produced by the fungus Fusarium roseum var. graminearum Snyder & Hansen was ingested and retained by the confused flour beetle, Tribolium confusum Jacquelin du Val, and the lesser mealworm, Alphitobius diaperinus (Panzer). F-2 persisted in the insects through metamorphosis and was detected after starvation and death. The amount of F-2 recovered from the insects increased with increasing F-2 concentrations in the insect culture media.