Centipedes and millipedes are both arthropods that belong to the order myriapoda, which denotes that these creatures have a “myriad of legs.” While some people might think that centipedes and millipedes are pretty much the same, you may be surprised to learn how different they actually are. They both have a lot of legs, but they look different, eat different things, and live in different environments. In this ultimate guide, we will help you learn to identify which of these creatures you are dealing with and give you great tips for controlling them around your home.
What do centipedes look like?
Centipedes are elongated animals with many body segments, typically 15 or more. On each of these body segments, they have one pair of legs. Although centipede means “100 feet,” the number of legs ranges anywhere from 30-354. Surprisingly the number of pairs of legs is always odd, so a centipede never actually has 100 feet. It may seem difficult for them to move quickly with all those legs, but centipedes have evolved to be very fast runners. Each pair of legs is slightly longer than the one before, so there is no overlap. This reduces the chance of colliding and allows them to move fast.
There are over 8,000 different species of centipedes that can be found in nearly every environment from tropical rainforests to deserts, and even in the Arctic Circle. Because there are so many different species, colors vary widely, but most of them are shades of reds or browns. They can also be different lengths that range from just a few millimeters to nearly 12 inches long. The centipede that most often is a household pest is scutigera coleoptrata, otherwise known as a house centipede. They typically have 15 segments, long antennae, and are light brown in color.
House Centipede (scutigera coleoptrata)
Are centipedes dangerous? Do centipedes bite?
Centipedes are poisonous, and they do bite. That being said, their bite is usually a minor nuisance to humans and normally only occurs when they feel threatened. Centipedes use fangs that are located behind the head, called forcipules, to deliver venom. These “fangs” are actually front legs with hollow tubes that connect to their venom glands that have evolved to perform the task of grabbing and then paralyzing their prey.
The bite of a large centipede may feel similar to a bee sting, but many small centipedes do not have a bite strong enough to even pierce the skin. While most centipede bites cause minor symptoms, some bites can be very painful and may cause severe swelling in sensitive individuals. Like many other types of insect venom, certain groups may react more seriously to centipedes. The very old, very young, and those with a known allergy to insect venom should be particularly cautious around centipedes. The most serious reaction, which occurs very rarely, is anaphylactic shock, which is life-threatening.
Where do centipedes live?
Centipedes (and millipedes) lack the waxy coating on their body that most insects have. This means that they will dry out quickly, and moisture is essential for their survival. Some places that meet their moisture requirements are soil, leaf litter, rotting logs, and under stones. When centipedes venture into homes, they most likely will be found in damp, dark places like basements, closets, and bathrooms.
What do centipedes eat?
It may surprise you to know that most centipedes are carnivores. Common prey for centipedes may include earthworms, amphibians, small mammals, spiders, and many other insects. They may occasionally eat plants, but studies have shown that plants are an unimportant part of their diet. Since centipedes mostly prey on other insects and pests, they can actually be very beneficial to have around the yard because they eat things like flies and cockroaches. If you can get over their creepy appearance and the shock of seeing them scurrying out from under things, centipedes can actually be helpful enough to tolerate their presence, though probably not in your home.
What do millipedes look like?
Like centipedes, millipedes are best known for their many legs. Millipede is Latin for “1000 feet,” though the record for most legs is currently at 750. The body shape of a millipede is long and cylindrical, and they have from 11 segments to over 100. Each body segment has 2 pairs of short legs that are attached to its underside. Unlike the centipede that moves quickly, millipedes are slow movers. The movement of their legs often makes them appear to be moving with a wave-like motion. Millipedes tend to be black or brown in color and different species can range from 2 mm to 35 cm in length.
American Giant Millipede (Narceus Americanus)
Are millipedes dangerous?
The majority of millipedes are harmless to humans, plants, and animals. Unlike centipedes who are predators, millipedes are detritivores, meaning that they eat dead and decaying plant matter. They are important decomposers, and some species will also eat fungi or suck plant juices. A very small minority of millipedes are predatory. Millipedes do not bite. When they are threatened, they will curl up in a tight ball to protect their soft undersides. Some may also secrete a nasty smelling liquid as a defense. Even this obnoxious fluid is generally harmless, though some people say it may irritate the skin.
Millipedes in Homes
Millipedes live in many different environments all over the world, but they need a moist microhabitat to survive. Most millipedes prefer to burrow in the soil. They will dry out quickly with a lack of moisture, so they do not often find their way into homes. If you find millipedes in your home, they are most likely to be in very moist areas like basements or crawl spaces. They typically cannot live in homes for very long and cannot breed in dry climates, so it is very rare that you will need to use chemical control for millipedes.
Centipedes vs Millipedes: A Quick Glance
- Both are arthropods with long bodies and many different body segments
- Both have many legs
- Both have one pair of antennae
- Both lack a waxy coating, so they require a moist habitat
- Centipedes have 1 pair of legs per body segment; Millipedes have 2 pairs per segment.
- Centipedes are fast movers that run; Millipedes are slow-moving creatures that prefer to burrow.
- Centipedes are venomous and can give painful bites when threatened; Millipedes are harmless and will curl up in a tight ball. They may also secrete a foul-smelling, but harmless liquid.
- Centipedes are mostly carnivores that eat other small animals and insects; Millipedes are mostly detritivores, but may do slight damage to some kinds of plants.
- House centipedes can often be found in homes; Millipedes are rarely found in homes.
Treatment and Control of Centipedes and Millipedes
Since centipedes and millipedes must live in a moist environment to survive, they usually will not last long indoors, the exception being the common house centipede. This means that it is often unnecessary to use chemical treatments, and it is instead more beneficial to employ prevention measures to keep them out in the first place. The following are things you can do now to prevent centipedes and millipedes.
Get Rid of Excess Moisture
- Water lawns in the morning so that they have a chance to dry out
- Don’t overwater flowerbeds
- Fix any leaky pipes, sprinklers, or spigots
- Aerate and dethatch the lawn to help with drainage
- Use a dehumidifier in your home if necessary, especially in basements or crawl spaces.
- Store firewood away from your home and off the ground
- Get rid of rotting fruits and vegetables from trees or gardens
- Remove moist debris like leaves, compost, or grass
Seal the Exterior
- Use caulk to seal small cracks and holes
- Expandable spray foam can be used to seal larger gaps
- Make sure that door and window screens are in good condition without holes or tears
- Check the weather stripping on doors, windows, and garages to ensure a tight seal
Residual Perimeter Treatments
A good residual pyrethroid will stop a variety of bugs from getting into your home, including centipedes and millipedes. Always follow label directions when using chemicals. Most recommend that you spray the foundation of your home 3 feet up from the ground and 3 feet out from the walls. This will ensure a good barrier. Pay special attention to possible entry points like cracks, crevices, doors, and around windows. Harris Home Pest Control is a great option that can be used indoors and outdoors, is non-staining, and will last a long time.
Since centipedes and millipedes are often found in lawns and yards, using a granular product can be effective. A product that contains bifenthrin can be spread over mulched flower beds, lawns, and other areas around the yard. Again, application of chemicals is rarely needed unless there is a major infestation that prevention techniques are not controlling well.
Insecticidal dusts are long lasting products that are great for hard to reach places. Since they are slow kill products, they work best when used in conjunction with other insecticides. Dust can be applied using a bellow hand duster to cracks and crevices, wall voids, behind baseboards, under sinks, around plumbing, around door frames, and behind outlets. Since it is most likely that centipedes and millipedes will be living in damp environments, choose a dust that can be used in moist areas.
Although they can look scary with all those legs, the majority of centipedes and millipedes have very little impact on humans. If an infestation does develop in your home or yard, Harris has the products and expertise you need to be able to tackle the problem. You can trust Harris because we are the oldest EPA registered brand in the United States. With Harris home pest control products, you can take back control of your home.