Flour Beetle in Bedroom: Causes and Prevention

You may be googling “flour beetle in bedroom” – help?! At first, you may even confuse this red flour beetle in your bed for a bed bug. Often we will show up to someone’s apartment for a NYC pest inspection because they have a flour beetle or Latridiidae beetle (minute brown scavenger beetles) in their bedroom, and they mistake it for a bed bug.

Keep in mind that if you found a small red beetle in your house,e it may be a red flour beetle, a confused flour beetle, or a minute brown scavenger beetle (Latridiidae).  The “red” and the “confused” beetles are a big problem at grain processing facilities, food warehouses, and homes.

In other words, this little pest can cause significant problems, so it’s essential to know how to identify it and get rid of it. Keep reading for more information on the flour beetle and how to prevent it from taking over your home.

Flour beetles love moisture and grain, especially if the humidity and grain are nearby. For example, if your apartment or house is humid and storing grain products, the beetles will happily thrive.

Even if you don’t live in a humid area, the beetle’s larval stage produces moisture within the food it’s feeding on, allowing the insect to thrive. It’s why if you see bugs in flour, you may want to throw it out.

It’s important to note that the larval stage eats most of the grain and doesn’t eat whole grain kernels. These pests will eat a grain that is in a fine powder form.

First, let’s go over the 2 common types of flour beetles and what they are. Second, we will cover your query “flour beetle in bedroom” – what to do?

What is a flour beetle?

Flour beetles belong to the Tribolium family. The two common types are the red flour beetle (Tribolium castaneum) and the confused flour beetle (Tribolium confusum).

Confused flour beetle - all over my house

They are beetles with a life cycle that lasts 40 – 90 days, depending on environmental conditions. First, the adult lays an egg, which ultimately hatches into larvae; after another 3- 10 weeks, it transforms into pupae, and the adult beetle emerges from the pupae.

It’s important to realize that one big difference between the red flour beetle and the confused flour beetle is that the red flour beetle has an antenna a three-segmented club at the end. In contrast, the confused flour beetle has an antenna with a four-segmented club.

Red Flour Beetle – Tribolium Castaneum

red flour beetle (Tribolium castaneum) in flour

The red flour beetle is a reddish-brown slender tiny common pest found in many homes, especially in the southern states, although they often turn up in NYC apartments.

These pesky critters often reside in pantries where they scavenge and feed on broken grains and other food items.

More importantly, aside from those people who experience allergic reactions, they are not known to be harmful to humans. However, they can do severe damage to your stored food and cost you money; since you will have to throw out the infested items.

In any event, If you do find yourself with a red flour beetle problem, there are various ways you can deal with the red flour beetle issue. Ultimately, you can avoid an infestation by keeping your home clean, rotating your flours and grains, and wiping down your cabinet shelves.

In summary, we will go over prevention and management at the end of the article.

Confused Flour Beetle – Tribolium confusum

Larvae and Confused Flour Beetle Tribolium Confusum

The confused flour beetle, like the red flour beetle, is also reddish-brown and slender. It’s also a common household pest found in kitchens worldwide. More importantly, you will discover beetles anywhere you store food, such as warehouses and factories.

They get their name, not because they wander around your house in a confused state, but because they are often confused with the red flour beetle.

The confused flour beetles are more often found in northern states, with a colder climate, although you can find them in the south. These little critters love to feed on anything made of starch, including flour, cereal, nuts, and pasta.

Not only will you find them infesting these items, but you’ll also see them in dried flowers, potpourri, herbs, and other places like museums.

The adult beetles are very active and can be very difficult to get rid of. They move around rapidly when disturbed and can be quite a nuisance.

The average life of an adult beetle is over one year. Females lay an average of 500 to 1,000 eggs, which go through a larvae stage and then a pupal stage before reaching adulthood.

Now that you have information about these flour beetles let’s talk about some differences between a flour beetle and a bed bug. You can learn everything about bed bugs within our other articles.

Grain Beetle VS Bed Bug (Flour Beetle VS Bed Bug)

NameRed Flour Beetle Bed Bug
Photo (Images not scaled to size)Red Flour Beetle Tribolium CastaneumBed bug,(cimex,Lectularius) Grain Beetle VS Bed Bug
Scientific NameTribolium CastaneumCimex lectularius
Adult Size 3 – 4 mm5 – 6 mm
ColorReddish BrownRed, burgundy, rusty red (depend on when it’s last blood meal was)
Life CycleEgg -> Larvae -> Pupae -> AdultEgg -> Nymph (5 stages) -> Adult
What Do They Eat?Flour, Meal, & nuts Blood
Do They Fly?Yes (sometimes)No
Do They Have Chewing Mouthparts?YesNo
Do They Bite Humans or Pets?NoYes (drink blood)

Grain Beetles in Bedroom: What to do

If you have pantry beetles in your bedroom, it means that you have some stored food products, museum specimens, pet food, dried flowers, or something other nearby that is infested with the grain beetles. In addition, If the kitchen is close to your bedroom, you may see some of these flour beetles in your bed.

A flour beetle can wander around a house, and in a few months, you can quickly become infested with these pantry pests. You can even find some of these flour beetles in your bed because they are scavengers.

If they do wander in your bed, then there is a chance that you get a mattress worm infestation from them.

Consequently, some people get an allergic reaction to the beetles and the debris they leave behind.

Incidentally, an allergic reaction will look like welts or rashes on your skin. To note, there have even been some people who have mistaken these allergic welts for bed bug bites.

What To Do If You Have Flour Beetles In Your Bedroom


The first thing to do is get a dehumidifier; this will help remove moisture and humidity from the air. Not only are the grain beetles attracted to moist areas, but they also cause moisture to build up inside of milled grains, which in turn causes mold growth.


Vacuum your entire house or apartment, in particular; pay special attention to cracks and crevices.

Pantry Inspection

Take everything out of your pantry, including pancake batter, bags of flour, pet food, birdseed, nuts, corn, and cereal. Inspect every item, and then vacuum each shelf.

If you find one infested item, you must throw out all of the other things, especially if you did not store them in airtight containers for flour and sugar.

If you don’t already have airtight containers for your flour, cereal, pasta, and pet food, then it’s time to purchase some. They can help prevent a pest issue from contaminating your entire cupboard.

After you vacuum the shelves, then wipe them down with a disinfectant. The flour beetles will leave droppings and shed skins on your frames, and you’ll need to clean up before you put anything back.

Life Cycle of the Flour Beetle

Tribolium castaneum life cycle

Egg – Usually hatch in 5 – 12 days

Larvae – They go through 5 to 12 stages (instars) over approximately 1-3 months

Pupae – Adults will emerge within 3-8 days

Adult – They can live between 1-4 years.

Where do Flour Beetles Come From?

There may be beetle eggs inside your flour, cereal, or other food product. The eggs are sticky, and the beetles lay them within the food product the beetle is feeding on. You risk getting a pantry pest infestation once you bring in some eggs or larvae.

If you have other pantry pests like weevils, learn more about how to get rid of weevils here!

Red Flour Beetle in Bed: What to do

If you find a red flour beetle in your bed, don’t panic. Start by finding the source. First, capture the bug on clear packing tape and email a photo to a local pest control company. It’s essential to get a proper ID.

If it is a flour beetle, then you’ll need to follow the steps above for “What To Do If You Have Flour Beetles In Your Bedroom.” You’ll need to do a deep cleaning and inspection of your pantry and closets.

In summary chemical pesticides are probably not the best option to control flour beetles. You won’t get rid of them until you clean and declutter your kitchen cupboards.

Do Grain Beetles Bite?

Grain beetles do not usually bite humans; however, since they have chewing mouthparts, one can accidentally bite you if its tasting things around them. They are not out to bite us, like bed bugs or ticks.

What Kills Flour Beetles?

First and foremost, the best way to get rid of a flour beetle infestation is to clean your kitchen thoroughly. In grain processing facilities, they use various bio-pesticides like Beauveria bassiana to decrease the population of flour beetles and their larvae.

In addition, Beauveria bassiana is a fungus that grows worldwide; it helps us fight against bed bugs, termites, flour beetles, and more.

In short, different strains of the Beauveria bassiana fungus vary in their killing capabilities for various insects. Check out this interesting study on the effect of temperature and the effectiveness of Beauveria bassiana.

Final Thoughts For “Flour Beetle in Bedroom” – Help!

It seems like every time you turn around; there’s another one! These tiny pests can be a real pain, invading your food storage and multiplying like crazy. Although they can cause an allergic reaction in some people, they are not known to bite us. So if you do see a flour beetle in your bed, just do a thorough inspection of any stored food products to see if you find a colony.

More importantly, you can quickly eliminate flour beetles with a small amount of effort. By understanding their habits and taking some simple precautions, you can keep these critters from becoming a problem in your home.

Flour beetles are attracted to moisture and grain, so the best way to prevent an infestation is by keeping your food products dry and sealed in airtight containers.