Flour Beetles

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Flour Beetles

• Commonly known as bran bugs

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Shared Characteristics

• Reddish-brown
• ? ¼ inch long
• Flat, shiny, reddish-brown
• Head is visible from above
• Chewing mouth parts
• They dont bite, sting or spread disease
• Notched eyes

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Red Flour Beetle

• Thorax has curved sides
• Last segments at the tip of the antennae are much
  larger
• Adults can fly short distances
• Mainly seen in warmer parts of the southern U.S

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Confused Flour Beetle

• Straight sided thorax
• Antennae segments increase in size from the base
  to the tip
• This beetle got its name because at first glance
  it looks so similar to the red flour beetle
• More common in the northern states

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Flour Beetle Life Cycle

• 7-12 weeks (egg ? adult)
• Females lay 300-400 eggs during a 5-8 month
  period. Eggs hatch within 5-12 days.
• Larval period at least 22 days
• Pupal period 8 days
• Adults emerge
• Adults live up to 3 years
• All forms of the life cycle may be found in
  infested grain products at the same time.

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Male or Female?
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Habits

• Adults are very active and will quickly hide when
  disturbed.
• Adults can be found on the surface or deep within
  food material.
• Adults invade storage containers and chew through
  storage bags.
• Flour beetles generally feed on foods in your
  pantry.

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• They are attracted to light.
• They prefer temperatures of 30 ºC.
• They are attracted to grains with high moisture
  content.
• They give off a bad odor and cause mold growth in
  the grain.

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Where are they found?

• Flour beetles infest flour and foods made of
  processed grain.
• They have been found in barley, cereals, corn,
  cornmeal, crackers, millet, oats, rice, rye,
  wheat, wheat bran, dried fruit, legume seeds,
  nuts, beans, milk chocolate, powdered milk,
  spices, sunflower seeds, pasta, cake mixes, dried
  pet food.

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Your Job

• Get into your lab groups and