Arizona’s Creepy Desert Noodles: Millipedes and Centipedes

I've lived in Arizona for a long time, and boy, do I have stories about the things I've found in my house. Here's a short list:

• mosquitoes
• house flies
• wolf spiders
• sun spiders
• Sonoran gopher snake (I wish I were kidding)
• a cactus wren
• scorpions
• a *goat (I'm not kidding)
• tarantulas

(There's a story behind the *goat.  I'll save it for another time.)

No matter how hard you try, sooner or later, you're going to get something weird in your house, too. I live in the country, so my list may be longer and crazier than yours.

With all these creepy-crawlies, there's one more that gave me a start: a ginormous centipede. Or a millipede. I'm not sure which one it was, but it was large and on the wall behind my office door.

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Are Millipedes And Centipedes The Same Thing?

This creature was about three feet long. At least, that's how I remember it. I'm sure it wasn't quite that big, but it was still impressively large. So, was it a millipede or a centipede? Are they the same thing, I wondered?

They're actually quite different, except they're both “creepy desert noodles with too many legs”. Millipedes and centipedes are both arthropods, but that’s where the family resemblance ends.

READ: Tarantulas, Rattlesnakes, Scorpions. Cochise County is Tough!

Arthropods, according to Wikipedia, "are invertebrates in the phylum Arthropoda." Both centipedes and millipedes have an exoskeleton and a body with "differentiated segments" and paired, jointed appendages.

As they grow, they go through stages of moulting, shedding their exoskeleton in favor of the new one growing underneath.

And here's a little factoid to keep you awake at night: they're in an extremely diverse group, with up to ten million species.

Millipedes are the slow, chill vegetarians of the bunch. They like to munch on dead plant material. Centipedes are fast, cranky predators armed with venom and attitude. Millipedes won't hurt us. Centipedes might.

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What's the Difference Between Millipedes and Centipedes?

According to AZAnimals.com, while they're related, millipedes and centipedes are a bit different from each other. You can think of millipedes as the introverts. They have rounder bodies, two pairs of legs per segment, and a tendency to curl up when bothered.

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Centipedes are the extroverts nobody asked for. You'll know them by their flattened bodies, one pair of legs per segment, and a habit of biting first and asking questions never. In reality, it's less of a bite and more of a pinch, according to the Arizona-Sonora Desert Museum.

Centipedes can deliver a painful venomous "bite", while millipedes don’t bite at all. Instead, millipedes just want you to go away, and they might release a stinky defensive fluid. It's gross, but not dangerous.

Where Do They Live And When Are They Most Active?

Unlike other arthropods, centipedes and millipedes don't have a waxy layer to deflect the heat, so they're only active in cooler desert nights. They spend their days underground or in cooler places. Like your air-conditioned house.

Both critters love moisture, so there's a good chance you'll find them after a desert thunderstorm, and under rocks, logs, mulch, and anywhere damp.

They tend to show up more after rain or during the monsoon season, when the soil is soggy, and it's safe for them to venture out.

Are They Dangerous To Humans Or Pets?

While centipedes are venomous and their bites can be painful, they're rarely serious unless someone has an allergy. Millipedes aren’t venomous and don’t spread disease. Pets might get irritated if they get one in their mouth, but that’s usually the worst of it.

READ: How Living In Arizona Changed My View On Desert Creatures

How Do You Keep Them Out Of Your House?

These days, I'm less freaked out when I find the desert has entered my house. Still, I don't want these-a-pedes in my house any more than I want snakes or tarantulas taking up residence.

The best way to keep them out of your home is to seal cracks, reduce moisture, fix leaks, and keep mulch or debris away from your home's foundation. If things get really bad, you can call an exterminator.

Basically, make your home the driest, least appealing Airbnb possible for these leg-ful intruders. If they still sneak in, a vacuum and a stern “nope” usually does the trick.