cosmopolitan(1) (spread by trade), of unclear origin(3)
primarily, granaries, grain elevators, flour mills, but capable to survive winter in temperate climes outdoors(1); adults have not been seen in flight, but they have been collected in light traps(4)
eggs laid singly or in small clusters in crevices in the food material during a 2-5 month period and hatch in 3-17 days; larva passes through 3-5 instars and makes a pupal cell attached to some solid object to pupate; typical life cycle takes 30-50 days; up to 7 generations per year; adults typically live 6-10 months (sometimes >3 years) (details in(4))
serious pest of stored grain; presence in household products is incidental and causes little concern(1); does not attack unbroken grain, but uses small lesions on the surface to gain entrance(4)
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