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Saw-Toothed Grain Beetles

Saw-toothed grain beetles common name is derived from the six saw-like teeth on each side of the first segment located behind their heads.  This is one of their most identifying characteristics.  In general, saw-toothed grain beetles are relatively small at only 1/8 of an inch in length.  They are thin, flat beetles that are dark brown in color.  Both adults and larvae feed on stored products including flour, bread, cereals, pasta, dried fruits, nuts, sugar and dog food.  Adults are not known to fly, nor are they attracted to lights.  Adults typically live 6 to 10 months, although they have been known to live upwards of three years.  Females lay an average of 45 to 285 eggs into cracks and crevices in food areas they are infesting over a period of four to five months.  Eggs are a shiny white in color.  Emerging larvae are about 1/8 of an inch long, yellowish-white in color and have 3 pairs of functional legs as well as 1 pair of false legs on their abdomen.  Larvae molt two to four times prior to becoming an adult.  A single life cycle from egg to egg can take as long as 375 days; however, it typically requires only 30 to 50 days to be completed.  Saw-toothed grain beetles and their larvae are capable of hiding in small cracks and crevices as well as the food they infest.

Controlling saw-toothed grain beetle infestations requires locating and eliminating all sources of infestation.  Alternatively, stored food products can be treated using heat at 125 degrees for one hour or cold of roughly zero degrees for a period of 24 hours. The infested area must then be thoroughly vacuumed and cleaned to eliminate any potentially spilled foods.  Applications of residual insecticide may be applied by a pest control professional to aide in the elimination of an infestation in order to prevent potential adults from re-entering the infestation area.  Food-attractant traps are available and are useful in determining areas of activity or monitoring activity after a cleanout and treatment have been completed.