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Warehouse Beetles

Adult warehouse beetles vary in size and coloration; however, they are typically around 1/8 of an inch in length and brownish black in color.  Warehouse beetle adults, unlike Khapra beetles are capable of flying.  Due to their close relation to other beetle species, it is recommended that samples be submitted to a professional for identification.  Warehouse beetles are insatiable feeders and have been reported consuming items such as seeds, dead insects and animals, cereal, candies, cocoa, corn, dog foods, flour, oatmeal, pastas, spices, wheat, barley and pollens.  Although they cannot feed on whole grain kernels, they are able to sustain themselves on broken kernels.  Both adults and larvae are tolerant to cold temperatures.

Females deposit up to 150 eggs in a single manner loose within processed foods or in the crevices of whole kernels.  Eggs hatch approximately 7 days later.  Larvae are 7-8mm in length.  Coloration varies from a whitish-yellow to a dark brown depending on the age of the larvae.  The top portion of the last 3-4 body segments are covered in thick tufts of setae or hairs.  Sensitive individuals that come in contact with or ingest the larvae may encounter a reaction to these hairs.  Larvae typically complete 6-7 molts depending on their gender prior to adulthood; however, larvae are capable of pauses in development which may last up to 2 years when necessary.  Pupation is completed in the final skin of the larvae and ranges in length from 4 days to 34 days depending on if delays occurred during development of the larvae.  Adults remain within the larval skin for up to a week before emerging.  Mating occurs soon after emergence.  Life span of an adult warehouse beetle is a maximum of 100 days with 9 to 50 days being most common.

As with a majority of the species of stored product pests, elimination of infested items is extremely important in controlling the infestation.  Thorough cleaning and maintained sanitation is also extremely important.  Applications of residual insecticides by a pest control professional may be necessary in some cases in order to completely eliminate warehouse beetle infestations.