Red Flour Beetle Facts & Information

Red flour beetles are shiny and reddish-brown in color, they have a flattened, oval shaped body and are winged. They will use their wings to fly short distances. Adults will grow to be about 1/8th of an inch in length. Red flour beetles have distinctive antennae that abruptly end into an enlarged three-segmented club.

The adult beetles are very active and move about rapidly when disturbed. The average life of adults is about one year. Females lay an average of about 450 eggs, which are small and clear white. The eggs are laid loosely on fine materials and broken kernels where the adults reside. The eggs are covered with a sticky secretion which the fine material adheres to. Fresh material placed in a grain bin will become rapidly infested if previous grain residue is not removed. Larvae (small brownish-white worms) hatch in five to twelve days and are full-grown in one to four months. Full grown larva are about three-sixteenths inch long and tinged with yellow. These larvae feed on fine materials and broken grain kernels. The larvae transform into small naked pupae, which are white at first and then gradually change to yellow and then to brown and shortly afterwards into the reddish-brown adult beetle. The period from egg to adult averages about six weeks under favorable weather conditions, but is greatly prolonged by cold weather, as is true of all grain pests.

It generally feeds on finely ground or broken starch materials, such as flour or meal. Adults and larvae feed on broken kernels and fine-grind materials in granaries, mills, warehouses, and other places where grain or grain products are stored. The red flour beetle is often found associated with the confused flour beetle. These two species are difficult to distinguish, particularly in the larval stage of development. The life cycle of the red flour beetle is usually shorter than the confused flour beetle. They are both flour beetles but are different species, so make sure you have proper identification from a Board Certified Entomologist so that you know you are getting the correct beetle treatments.