Tribolium confusum, is one of the most common insect pests of stored food within homes throughout the country, and they are particularly common in the eastern US. This species is more commonly known as the “confused flour beetle,” and according to a recent nationwide survey of pest control professionals, this species is the fourth most commonly controlled pantry pests within homes. The confused flour beetle is closely related to another common pantry pest known as the red flour beetle, which the above mentioned survey found to be the sixth most commonly controlled pantry pest in the US. These two beetle pest species are very difficult to tell apart, especially during their larval stages of development. The red flour beetle is most abundant in the south, while the confused flour beetle is most abundant in the north, but the latter has a worldwide distribution, and is a common pantry pest in all areas of the US.
Adult confused flour beetles are very active and their presence within a home indicates that an infestation within food products has been established. Adults can be recognized for their shiny, flattened, oval, and reddish-brown bodies which measure around 1/7 of an inch in length. Under magnification, adults have small holes covering their head and upper body. Adult females lay their eggs directly in food products like flour, cereals, dried beans, peas, peppers and fruits, shelled nuts, spices, chocolate, and even certain pharmaceuticals. Eggs are white and sticky, causing flour to adhere to the outer surface, and in some cases, eggs are found stuck to the interior side of food packages. Once larvae emerge from eggs, they eat their way into kernels of grain, but they sometimes leave their initial harborage to find more favorable development sites nearby. Larvae are cylindrical, slender and white with a yellow tint. They are around 3/16 of an inch long at maturity, and they reach adulthood in as few as 30 days in optimal conditions. Confused flour beetles are easily the most common pests of processed flour, and luckily, eating food contaminated with these insect pests will not cause medical harm.
Have you ever found insect eggs in stored food products within your home?