Sawtoothed Grain Beetle

Actual Size: ⅛”

Characteristics: Slender, flat and brown

Legs: 6

Antennae: Yes

Wings: Yes, but do not fly.

Habitat: Found in food manufacturing plants or homes; infest dried goods, bread, and nuts.


  • Get their name from the 6 tiny sawlike “teeth” on each side of the body.
  • Incapable of attacking sound grain, preferring dust and crumbs.
  • Typically enters homes in infested products from grocery stores.

Sawtoothed Grain Beetles in San Juan

The sawtoothed grain beetle is a common stored products pest found throughout the nation in homes, grocery stores, food warehouses, and grain storage facilities. Similar in appearance to the merchant grain beetle, the merchant grain beetle has the ability to fly, while the sawtoothed grain beetle does not. Adults find their way into stored grains, flour, sugar, nuts and other dry material of plant origin through cracks and crevices of imperfectly sealed containers.

They are incapable of attacking sound grain kernels and often occur in food previously infested by other stored product pests.Their flattened body allows them to easily penetrate broken kernels of grain and packaged materials. Not only do they contaminate food, they often cause mold problems due to moisture build up.

Sawtoothed Grain Beetle Habitat

Sawtoothed grain beetles are commonly found in food manufacturing, storage, and retail facilities, as well as in home pantries. This stored product pest feeds on breads, cereal, dry pasta, dried meats, candy, nuts, and other dry goods. A single female can lay up to 250 eggs within cracks of kernels of grain. As with other pantry insects, it is the larvae that do most of the damage, however, the adult is most commonly encountered. A typical discovery of a saw toothed grain beetle infestation occurs when adult beetles are discovered crawling around a pantry area.

Sawtoothed Grain Beetle Behaviors, Threats or Dangers

Sawtoothed grain beetles are not known to carry or transmit any diseases to humans and do not bite or sting. They are nuisance pests, and will contaminate and damage food that is stored in the home. Adults can readily enter sealed cardboard boxes and soft plastic packaging. Sawtoothed grain beetles typically enter homes in products purchased from grocery stores which are already infested with larvae or adults. The primary infestation usually originates at the manufacturing facility where the product was produced.

If you have sawtoothed beetles in your San Juan property, contact your local exterminators for help.