Red Flour Beetle (Tribolium castaneum)
Red Flour Beetle Traps
Red Flour Beetle Description
Red Flour Beetle Adults: These small beetles are reddish brown, and about 3.5 mm (0.15 inches) long. Red flour beetles can be differentiated from Confused flour beetles by the last four segments of the antennae.
On Red Flour Beetles, the last three segments of the antennae are abruptly enlarged to form a club. Confused flour beetle are gradually enlarged towards the tip. Adult Red Flour Beetles of this species fly in warmer temperatures, usually above 29°C (85°F).
Eggs: Oval, ivory in color and only visible under microscopic examination of flour products.
Larvae: The immature stage is approximately 4-5 mm (0.25 inches) long, white to yellowish in color, and wiry in appearance. The last abdominal segment ends with two prominent points.
Pupae: Pupal cases are white to yellowish in color and nearly the same size as adult beetles. The tip of the abdomen ends with two prominent points.
Red Flour Beetle Life Cycle
Female red flour beetles will deposit 200-450 eggs in food during a 1-3 year life span. Eggs hatch in 5-12 days, and the larvae can mature within 30 days in warmer months or as long as 120 days in cooler months. The life cycle of this species is shorter than the Confused Flour beetle. The reproductive rate, as a result, is usually higher as well.
Red Flour Beetle Damage & Detection
Heavy infestations of flour by this insect may cause the product to turn greyish or mold prematurely. This insect can also give a citronella-like smell and taste from its scent glands to the material infested. They are primarily pests of flour, but also feed on processed beans, nuts, spices, chocolate, and pharmaceuticals. Both adults and larvae cause damage.
Red Flour Beetle Facts
Similar species include confused flour beetle (Tribolium confusum), black flour beetle (Tribolium madens), American black flour beetle (Tribolium audax), broadhorned flour beetle (Gnatocerus cornutus), and longheaded flour beetle (Latheticus oryzae).
Other common names include rust-red flour beetle, red brown rice flour beetle, and small flour worm.
Red flour beetles initiate flight at temperatures above 20°C (68°F).
The pheromone that attracts red flour beetle also attracts similar species including:
Confused flour beetle (Tribolium confusum)
American black flour beetle (Tribolium audax)
Destructive flour beetle (Tribolium destructor)
Kashmir flour beetle (Tribolium freeman)
Black flour beetle (Tribolium madens)
Red Flour Beetle Monitoring Tips & Tricks
Red Flour Beetle Monitoring Guidelines
Lure
BULLET LURE® Contains aggregation pheromone to attract male and female beetles.
PANTRY PATROL® Pheromone /oil dispenser. Contains grain-based food attractants and aggregation pheromones to attract males and female Red Flour Beetle.
STORED PRODUCT BEETLE Lures are food bait and pheromone lures that was specifically designed to make the Pantry Patrol gel into a tablet form.
ALL BEETLE TRAP READY-TO-USE TRAY is a preloaded accessory of the ALL BEETLE TRAP that contains either the PANTRY PATROL Pheromone/oil dispenser or the STORED PRODUCT BEETLE LURE and glueboard.
Lure Storage
Keep unopened BULLET LURES, PANTRY PATROL pheromone /oil dispensers, READY-TO-USE TRAYS, and STORED PRODUCT BEETLE LURES in cool storage for 12 Months or in refrigeration for up to 24 months before using or discarding.
Trap Designs Used with Lure
ALL BEETLE TRAP consists of three parts: A clear lid, blue base, and snap in tray. This device can be paired with many different types of attractants available by Insects Limited depending on the insect you are monitoring.
PANTRY PATROL “CORNER” pitfall traps contain a triangular pit to receive a full dispenser of pheromone /oil. Dust cover is incorporated into cardboard packaging.
Red Flour Beetle Traps
Red Flour Beetle Trap Placement & Use
Trap Placement Techniques
Red Flour Beetle Pheromone traps can be placed year-round but are especially recommended when temperatures exceed 12.5°C (55°F). Floor pheromone traps like the All Beetle Trap and Flat Trap are most effective at capturing Red flour beetles. In areas such as a pantry or home, place one or two pheromone traps per room.
In commercial areas such as warehouses or retail stores, place pheromone traps 2–5 m (5–15 feet) apart to determine the presence or absence of Red flour beetles. Increase pheromone trap density to 2–5 m (5–15 feet) apart to help locate the source of red flour beetles.
Red flour beetle pheromone traps are best utilized in areas that store dried goods such as food, grains, seeds, nuts, animal feed, or pet food.
Trap and Lure Maintenance
Replace red flour beetle traps when glue is filled with insects or becomes dusty. Replace pheromone lures every 90 days. Replace all pheromone lures in a location at the same time. Do not cut the cap off the bullet lure. Do not stagger lure replacement over several weeks. Record date and number of catches to identify trending information.
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Red Flour Beetle Behavior
Red Flour Beetle FAQs
What do flour beetles look like?
Adults are small beetles that are reddish brown, and about 3.5 mm (0.15 inches) long. Red flour beetles can be differentiated for Confused flour beetles by the last four segments of the antennae.
On Red Flour Beetles, the last three segments of the antennae are abruptly enlarged to form a club Confused flour beetle are gradually enlarged towards the tip. Adults of this species fly in warmer temperatures, usually above 29°C (85°F).
Eggs are oval in shape, ivory in color and only visible under microscopic examination of flour products.
Larvae are the immature stage and are approximately 4-5 mm (0.25 inches) long, white to yellowish in color, and wiry in appearance. The last abdominal segment ends with two prominent points.
Why are their flour beetles or flour weevils in my flour?
The small (3.5 mm), oblong red or brown bugs that you see in your flour are most likely either the red flour beetle, Tribolium castaneum or the confused flour beetle, Tribolium confusum. Lots of times, people may refer to them as flour weevils, but the term weevil is often used as a generic term for small bugs in dried food goods.
The likely reason that they are in your flour is that you purchased the flour with them already in there and brought them home with you, or they were already in some other food good in your pantry and they moved over into the flour.
These beetles use their antennae to locate potential food sources and the females will lay their eggs inside of food containers or right next to food containers. When the tiny eggs hatch, the larvae will crawl right into paper flour sacks or right into many other types of food storage containers. Then they feed and grow, up to the point where new adults emerge and reproduce right in the flour.
How to get rid of flour bugs or flour beetles?
The use of pheromone traps, otherwise called pantry beetle traps, can indicate the presence of flour beetles as well as where the beetles are coming from.
A visual inspection of flour, pet food or other dried food in the vicinity of the pheromone traps containing the most beetles can reveal specific items containing larvae, pupae and adult beetles. Once the source of the infestation is found, it should be sealed and disposed of or it should be frozen, such as with insect freezer treatment bags for a weeks time to kill any remaining live insects.
Red Flour Beetle Traps
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