Texas is full of sharp things: cacti, mesquite, porcupines. Even our grass has evolved to poke. Ours is not a land over which to freely run barefoot, and here you must treat every nook, cranny, and woodpile with the assumption that there is a rattlesnake nest inside it (this also applies to pool noodles and toilets). To grow up in Texas is to learn early on that you can’t just go touching things all willy-nilly. If a wild animal lives here, there’s a good chance it can hurt you, even—perhaps especially—if it’s cute.
Which is to say that ’round these parts, the cutest caterpillars are sometimes the last caterpillars you want to come in contact with your skin. Perhaps the fuzziest of them all is the larval form of the Southern flannel moth (Megalopyge opercularis). With thick, furry-looking hair in shades of brown, gray, and white, this caterpillar resembles an itty-bitty baby bunny—if that baby bunny had no face and seven pairs of legs instead of paws. Unfortunately, its hair obscures shorter spines that are filled with venom and will cause a painful, blistering, throbbing skin rash. “Brushing up against it delivers a little bit of venom, but accidentally sitting on one delivers a lot,” says Scott Egan, an associate professor of biosciences at Rice University. “This thing really hurts, and is likely the worst sting you can receive from a caterpillar in our region. The pain has been compared to blunt-force trauma or a broken bone.”
Often called a puss caterpillar or asp, this tiny (it grows to just over an inch) but terrifying insect has also been described as a “disembodied mustache” and a “toxic toupee.” Perhaps the cutest thing about it is that its hair swirls up like a faux-hawk, which Texas Parks and Wildlife says only reinforces “the troublemaker label.”
Fuzzy caterpillars are the juvenile forms of various moths. Some moths have “fur” that’s only mildly irritating, but those squares don’t compare to the Southern flannel moth, so named because it’s draped in warm and cozy outerwear not unlike something Kurt Cobain would wear. Further adding to its rock and roll image, the Southern flannel moth only lives about eight days into adulthood, just long enough to lay or fertilize eggs—thus truly living by the old adage, “Better to burn out than to fade away.”
The larval stage lasts much longer, from six to seven weeks, the last two of which are when the caterpillar is at its cutest. Not only does it have that adorable swoop of furry hair, but when it poops, it propels the excrement away from its body. That’s right, folks. This caterpillar flings tiny turds out of its cute round butt. It’s a fuzzy li’l poop cannon! Life on earth (and especially in Texas) is beautiful and miraculous.
The asp feeds on leaves and spends most of its life clinging to shady oak and elm trees. This preference contributes to the species’s abundance across forested parts of the state and to its rarity in regions with sparser vegetation, such as West Texas and the Panhandle. Once it has eaten and pooped a sufficient amount, the asp spins a cocoon, from which it will emerge as an adult moth. The transformation usually takes about two weeks, depending on the time of year and temperature. Then the moth has a week or so to lay or fertilize hundreds of eggs before lights-out.
Despite its brief lifespan, the Southern flannel moth gets a lot of media attention, specifically because of the caterpillar. Every few months, some outlet warns against coming in contact with the cute creature, just as I am doing now. Often this is via local news outlets, which issue annual reminders during Texas’s more caterpillar-heavy times of year (usually summer and fall). But sometimes the national media joins in, perpetually bewildered that something this cute could also be harmful. It’s often described as “the most venomous in the nation,” though that might be a stretch. “The data are truly hard to come by,” says Egan. “We would need to systematically compare the pain induced by each and every caterpillar in North America, which has not been done to my knowledge.” But it’s definitely up there. No matter how venomous it is, the asp is only a danger to those foolish enough to touch it. (Our condolences to entomologists like Egan, who have to work up close with these bad boys all the time. “I have been stung a handful of times on the hands, arms, and face!” he says.)
More than anything, this caterpillar offers a crucial lesson for anyone making their home in Texas. The takeaway is one that applies to everything from raccoons to jellyfish to ants: if you don’t know for certain that it can’t kill or maim you, always assume it can.