Household Bugs -- Are Centipedes Poisonous?

Are Centipedes Poisonous?

We get this question a lot, and it has been addressed in previous posts. Centipedes are those speedy little critters that live in your basement and run out from under piles of laundry on the floor, or from whatever you might have on the floor. They tend to pop up unexpectedly, and they have a lot of legs, and they're really fast. There's something about that combination that doesn't appeal to humans.

So are they poisonous? Yes, but you really don't have anything to worry about! The brown centipedes in your house are essentially harmless, though if you picked one up and messed with it, and basically insisted that it bite you, you would feel a little sting.  So don't freak out! As we said before, the centipedes in your house aren't going to come swarming up on your bed at night and chew you to death (although that would be pretty cool -- not for you, but for everyone else).

Now there are some centipedes in the world that can REALLY bite. You'll never find one in your basement, since they live in wild and natural places. Some of these big guys -- which can grow to be several inches long -- can deliver a really painful bite that in exceptionally rare cases can kill an individual already prone to heart attacks. Here's one of them, a beautiful animal known as Scolopendra cingulata:

image public domain at wikimedia.org

Ain't it cool? If you find one of these, you're lucky. If it finds you, then maybe not so much.


Anyway, the individuals who really have to worry about that centipede bite are the cockroaches, silverfish, and other little bugs that can form part of the centipede's diet. The other part of the centipede's diet? Cockroach eggs. Yummy, right? But think about it -- those freaky-looking centipedes are doing you a HUGE favor every day and night. They're basically part of the clean-up crew that takes care of undesirable insects, living and dead, that would otherwise pile up in your house.

Here are a couple of centipedes you won't find in your house:

This beautiful animal lives in Hawaii, where its habitat is volcanic soil. Before you ask, yes, it's poisonous too. But please remember that it's poison is the result of eons of evolutionary development, and is meant for eating and self defense, NOT for attacking you!

This large centipede was photographed in Oman. It has a cool fake "head," with split end that a predator like a lizard or a bird might mistake for the head

The little brown centipede that lives in your basement is known scientifically as Scutigera coleoptrata, although depending on where you live it could be one of several other closely related species. The genus ("group") of brown centipedes originated in southern Europe, but once ships started sailing of and docking in foreign lands, the hitch-hiking centipedes (and lots of other critters) found happy homes in all parts of the world.

Your basement centipedes have 15 pairs of legs. The pincers that deliver the venom are actually modified legs, which is likely the case with all insect appendages, from mouthparts to antennae -- as different forms evolved, they adapted the many legs that their ancestors had for specified uses.

So yes, centipedes are venomous -- but in a pretty cool way. Often they will withdraw after biting prey to let the sting take effect. They can also distinguish between easy prey and dangerous insects like wasps. They're selective about who they try to eat, so your chances of being hunted and attacked by your house centipedes is zero.

So yes, they bite, and no, it's not a big deal.

Centipedes eat a lot of harmful bugs, so in general you should give them a pass and focus on killing the bugs that can really impact your life, like termites and roaches.

And remember -- it could be worse. Your basement could be full of these:

More Questions about Household Bugs? Click here for a ton of photos and information!

all images courtesy of wikimedia commons