The confused flour beetle attacks stored grain products such as flour, cereals, meal, crackers, beans, spices, pasta, cake mix, dried pet food, dried flowers, chocolate, nuts, seeds, and even dried museum specimens. This beetle is one of the most important pests of stored products in homes and grocery stores. The confused flour beetle apparently received this name due to confusion about its identity; it is very similar to the red flour beetle. It has worldwide distribution in cooler climates. As such, in the U.S., it is more common in the northern states.

Although small, about 3.5 mm long, the adults are long-lived. The confused flour beetle is reddish brown in color, and its antennae become gradually club-like, the "club" consisting of four segments. The antennae of the red flour beetle has a distinct 3-segmented club. The thorax of the red flour beetle has slightly curved sides, while the sides of the confused flour beetle’s thorax are more parallel.

The red and confused flour beetles live in the same environment and compete for resources. The red flour beetle may fly, but the confused flour beetle does not. Eggs, larvae, and pupae from both species are very similar. The eggs are white, microscopic and often have bits of flour stuck to their surface. The slender larvae are creamy yellow to light brown in color. They have two dark pointed projections on the last body segment. These beetles can breed throughout the year in warm areas. The life cycle takes from 40 to 90 days, and the adult can live for three years. All forms of the life cycle may be found in infested grain products at the same time.

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