Adults of these two beetles are reddish brown. Each antenna of the red flour beetle has a three-segmented club; the confused flour beetle’s has a four-segmented club.
Development. Eggs are laid directly on flour. Larval development is completed in 19 to 22 days. The number of larval instars ranges from 5 to 11. Pupae are formed in sheltered locations in the infested material; pupal period is four to 6 days. Adults live for about three years, and females lay eggs for more than a year.
Habits. These beetles infest grain, flour and other cereal products, milk chocolate, dried milk, and hides. Adult red flour beetles can ﬂy short distances, but confused flour beetles have not been observed to fly.