It seems to be the season for the march of 1,000 feet. I am referring to those worm-like creatures that seem to find their way into every crevice of your home, pitifully ending up under your feet if you’re not careful.
I’m talking about millipedes, of course. We find them climbing the walls, covering the sidewalk, and hiding under leaf piles. These flexible tubes with endless legs are arthropods; relatives of insects and spiders. They are in the same class as centipedes, but with very different characteristics.
There are close to 12,000 millipede species found worldwide and approximately 50 species in Florida. The average millipede can range between one and four inches long, and have several hundred feet that are paired. Millipedes have hard, round bodies with an average of 20 body segments with two pairs of legs per segment.
Millipedes are commonly confused with centipedes. Both are long, worm-like creatures, have segmented bodies and multiple legs, and live in mulch. But, that’s where the similarities end.
Millipede or Centipede?
The millipede is a slow-moving detritivore, which means it eats organic and dead plant material. It does not sting or bite, and its signature defensive move when threatened is to curl up into a spiral.
The centipede, however, is opposite in almost every way. It has only one pair of legs per body segment (remember, millipedes have two pairs per segment), and moves quickly. It is a carnivore, which means it feeds on insects.
And, the centipede can both sting and bite! So, it would be wise to be able to tell the difference between these diplopods.
Common Millipedes in Florida
Common millipedes in Florida are the Florida ivory millipede (Chicobolus spinigerus), the North American millipede (Narceus americanus), and the invasive yellow-banded millipede (Anadenobolus monilicornis), also known as the yellow-striped millipede.
Florida Ivory Millipede
The Florida ivory millipede is a solid-dark color with lighter underbelly and legs. This millipede species is large, reaching up to 3.5 inches long. They are often raised and sold as household pets. They do have a unique defensive mechanism in addition to coiling up in a ball. This millipede can secrete a noxious drop of hydrogen cyanide at will. The chemical can burn or cause an allergic reaction. However, it will only release the toxin if it feels threatened. You can handle the millipede, just be sure to be gentle while doing so.
North American Millipede
Like the ivory millipede, the North American millipede is also large. It has a dark-brown body with deep-red stripes. This millipede is also referred to as the “rust” or “iron” millipede.
The yellow-banded millipede looks like just like its name. It has bands of yellow around a dark-colored body, and dark-red legs. This is a large millipede, but does not have the ability to secrete toxins. While the toxin wards off potential predators, it might have another unusual use in nature. Scientists have witnessed monkeys rubbing these millipedes on their fur as a way, possibly, to ward off biting insects.
Native to the Caribbean, the yellow-banded millipede was discovered in Florida in 2001. Since then, the millipede has established itself throughout Florida.
Watching millipedes move is mesmerizing. Although they have many pairs of legs, only a few are required for walking. So, you see a short-wave pattern created by the legs as they stroll along the ground. However, if the millipede is burrowing through mulch or soil, all the legs are engaged, and a long-wave pattern is created.
A good way to observe the millipede walking is to put it on a piece of glass and watch it move by looking up through the bottom of the glass.
As mentioned above, millipedes are detritivores, which makes them beneficial organisms. They are an important part of nature’s clean-up crew, recycling nutrients back into the ecosystem as they feed. Millipedes are second only to earthworms in their ability to break down organic matter. But, rest easy: millipedes pose no threat to your veggies, flowers, or other landscape plants.
We have unintentionally and unknowingly created the perfect habitat for the millipede. We landscape around our homes and fill areas with mulch. This is a good thing, and one of the nine principles of Florida-Friendly Landscaping™. However, those landscape plants drop leaves, adding to the organic matter on which millipedes feed. We also water our landscape, creating a warm and moist environment, perfect for millipedes to live, feed, and reproduce.
With abundant rains or too much irrigation, though, the millipedes are literally flooded out of their normal habitat. The excess water drives them from their underground homes where they come to the surface, looking for a moist, but less-saturated living environment. Often, they find their way into our homes, simply by accident. Unfortunately, this is going from one extreme to another. The house is too dry and the millipedes slowly desiccate and die as they try to find their way to suitable habitat. The best thing to do with a millipede in your house is to pick it up or sweep it into a dustpan and place it back into the mulch.
The sheer number of millipedes present at certain times of the year can be annoying to any homeowner. However, they pose no harm to us, are beneficial organisms, and important to nutrient recycling. Knowing that, hopefully we all will view the multitudes of millipedes as the marvel that it is.
- UF/IFAS EDIS: Pillbugs, Sowbugs, Centipedes, Millipedes, and Earwigs
- UF/IFAS EDIS: Pests Associated with Mulch and Moisture