The ArthroBlogger
Fun stories. Random facts. All the arthropods.
Don’t Touch the Disembodied Mustache
If you’ve ever seen a mustache crawling up a tree, chances are you actually found yourself face-to-face with a Southern Flannel Moth caterpillar. These incredibly fluffy larvae grow up to be equally fluffy moths and live everywhere from Texas to Florida and up to New Jersey in the United States. Now that I’ve finally seen a luna moth, this fuzzy fellow is next on my bucket list of moths I must see in person.
You can look for them in local trees and bushes, but don’t touch – these caterpillars (quite tragically) are anything but cuddly. Those luscious locks hide poisonous spines that administer burning stings and swollen rashes. This painful defense mechanism earned them the nickname of “asp caterpillar” in reference to venomous snakes of the same name. If you are stung, applying ice pack to the rash is recommended, as well as using tape or tweezers to remove any spines still stuck in your skin.
Southern Flannel Moth caterpillars actually have a ton of nicknames. You may hear them called “woolly slugs,” “puss caterpillars,” “possum bugs,” and my personal favorite because it’s what I call my dog a lot: “perritos,” the Spanish word for puppies. With each molt, perritos (of course that’s what I’m calling them now) typically fade from yellow or brown to white and get progressively hairier until it’s time to pupate, and they typically feed on the leaves of common deciduous trees as they grow.
Perritos tend to build their cocoons on their host trees (the trees they eat from), other nearby plants, or on the sides of buildings. As they pupate, they shed their fluff and pack it into a bump in the cocoon called the hair pocket. I mean, I guess that’s easier than pausing metamorphosis to unzip the cocoon and dump all that hair out, right? Interestingly, Southern Flannel Moths do not emerge bald but are fluffy once more by the end of their pupation.
The perrito’s tough cocoon will protect it throughout the winter or summer, releasing the adult moth in early summer or fall for two generations of moths each year (or three in the Deep South, where the climate is warmer year-round). After the moth flies away, the empty cocoon persists for a long time and can be used as a shelter for other insects or spiders.
As adults, Southern Flannel Moths no longer possess poison spines, but they still don’t have much time for being cuddled: female moths will lay hundreds of eggs just days after completing their metamorphosis. The eggs take about a week to hatch, and then American parks are filled with crawling, poison-tipped mustaches again.
You may be wondering, “why are these moths so fluffy, anyway?” Well, apart from just making them look cute, moth fur (really setae, or fancy, hair-like scales) keeps the insect warm but also pulls off easily so the moth can escape if it gets stuck in a spider web.
That’s right, moth fluff is both fashionable and practical. Is God the master tailor, or is God the master tailor? That, or He thought it’d be funny to use the fur He’d set aside for the naked mole rats on moths instead. Either way, just one look at these fluffy insects will tell you He has a knack for subtle beauty – and of course, a sense of humor.
The ArthroBlogger 