Eight common insect pests - Red flour beetle

Red flour beetle

This pest is found in stored grains and oilseeds on farms and in primary elevators throughout the prairie provinces and most of Canada. Despite its name, the red flour beetle is more common in elevators and farm bins than in flour mills.

Appearance and behaviour

The adult:

  • Is reddish brown
  • Is 0.4 centimetres long
  • Flies in warm weather or may be blown by the wind into farmhouses or other buildings

Larvae and adults feed on broken kernels.


Complete development from egg to adult takes about 28 days under optimal conditions, that is, when the temperature of the grain is 31°C and the moisture content is 15 percent. Slower development occurs when the moisture content is as low as 8 percent.

The females lay 300 to 900 eggs loosely on top of a grain mass or in flour. Hatching produces worm-like larvae, whitish in colour with pale brown bands.

Red flour beetle image

dorsal view of the red flour beetle More on the red flour beetle
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