Sawtoothed grain beetle
Oryzaephilus surinamensis (L.)
Primary pest; grain feeder
- Adults are small, brown, slender beetles, about 3 mm in length with serrated sides on pronotum.
- Adults are very similar morphologically to merchant grain beetle; may be separated from merchant grain beetles based on the width of the temple (narrower in merchant grain beetle).
- Larvae are white to pale yellow and flattened.
- Merchant grain beetle (Oryzaephilus mercator)
- Foreign grain bettle (Ahasverus advena)
- Affects oats (beetle is most often found here), wheat, barley, animal feed, flax, sunflower
- Affects milled and processed products, dried fruit, packaged foods
- May attack a wide variety of foods found in homes, but this may be misidentification of O. Mercator (merchant grain beetle)
Signs of infestation
- Severe infestations can cause grain to become overheated contributing to further damage.
- Beetles are capable of rapid population buildup in large bulks of grain in heated buildings.
- Damage is generalized and not necessarily identifiable as coming from this particular species.
- Both adults and larvae may feed on grain dust and larvae preferentially feed on the germ.
How to control
- Is found worldwide and across Canada.
- Is found in granaries, warehouses, elevators and food mills
- Is not able to feed on sound kernels, but is able to attack even slightly damaged grain
- Is one of the most common grain feeding insects found in grain stored on Canadian farms.
- Pupation occurs either freely or within a cocoon consisting of particles of grain.
- This species requires high temperatures, but it can tolerate low relative humidity.
- Sawtoothed grain beetle is more cold-hardy than the merchant grain beetle.
- Species is able to survive Canadian winters in unheated structures.
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