MTPR

Bug Bytes: Centipede Or Millipede?

Jul 7, 2019

So you’re digging in the garden and see something crawling in the freshly turned soil. With its many legs, it’s clearly not a worm. But what is it? A millipede or a centipede?

Both have long, segmented bodies and lots of legs. But despite these visual similarities, they could not be more different in terms of diet and behavior.

Millipedes are leggier, having 4 legs per body segment to the centipede’s mere two legs per body segment. Millipedes’ legs are typically positioned under their bodies, while centipedes’ legs go out to the sides. And millipedes tend to be round or more tubular in shape, while centipedes are generally flatter.

But when it comes to getting a meal, that’s where the differences really come into play. Millipedes are slow. When you eat decaying organic matter, there’s no need for speed.

Centipedes are carnivorous racecars in comparison. Speed, coupled with a venomous bite, makes them extremely capable predators that can tackle a wide variety of prey.

If disturbed, millipedes will often curl into a coil — using their hard exoskeleton to protect their softer underside and legs. If further provoked, some millipedes can discharge a smelly and distasteful liquid that can also stain or irritate your skin.

Centipedes, on the other hand, will use their speed to flee the scene, but also have the ability to deliver a painful bite.

So the next time you’re digging in the garden or checking out what’s under a rock or log — are the legs out to the side or under the body? It is fast or slow? Did it curl into a coil or quickly run away? Such quick observations will help you determine which of “the pedes” you’ve found.

Bug Bytes is made possible by the Missoula Butterfly House and Insectarium, and Montana Public Radio. This show is also supported by funding from the Greater Montana Foundation: Encouraging communication on issues, trends and values of importance to Montanans.