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Red and Confused Flour Beetles

Although very similar in appearance, red and confused flour beetles do have a few characteristics that allow for identification.  Antennae on the confused flour beetle tapers into a four segmented club on the end whereas the red flour beetle has a three segmented club without the tapering.  In addition, the body segment directly behind the head on these beetles also has differences.  The confused flour beetle has very straight sides to this segment whereas the red flour beetle has a bowed appearance.  In general, the beetles share many characteristics including their red-brown color, slender bodies and 1/8 of an inch length.  Unable to feed on whole grains, flour beetles are a major pest of flour, dried fruit, nuts, chocolate, medications, spices and rodent baits.  Heavily infested flour has a foul odor and awkward taste due to secretions from the beetle’s scent glands.  Both confused and red flour beetles are attracted to light; however, only the red flour beetles fly.

Adults of both beetles have a life span of two to three years in which females produce 300-500 eggs.  The sticky clear to white eggs are laid in small groups of two to three eggs daily along cracks and bad seams.  Eggs incubation time is roughly five to twelve days.  The larvae are yellowish-white in color and are 1/8 to ¼ inch in length.  A darkened section at the rear of the body is not segmented and has immovable spines.   Development is completed in about 30 days and includes as many as twelve molts.  The entire cycle, egg to egg, is completed in less than 90 days.  Under ideal conditions, flour beetles are capable of producing four to five generations a year.  One of the most common of the stored product pests found within homes, infestations may include areas such as cupboards, cabinets, closets, shelves and pantry.  Items stored in these areas will need to be thoroughly inspected when an infestation is suspected.  Male pheromone traps are available and may be utilized to both detect and monitor areas of infestation.  Items determined to be infested should be promptly discarded or heat treated at 120 degrees for several hours.  Thorough cleaning and vacuuming of cracks and crevices should also be completed once areas of infestation have been located.  Upkeep of sanitary conditions in which spilled items are promptly cleaned up is important when working to resolve a flour beelte infestation.  In addition, storage areas and other sites of infestation may necessitate treatment by a pest control professional, with a liquid or dust application of insecticide in order to resolve the infestation.