Cicadas Fall Prey to a Psychedelic-Producing Fungus That Makes Their Butts Fall Off

This ‘zombie’ fungus isn’t going after the bugs’ brains—it’s after their genitals

A cicada with white fungus growing out of its butt sits on a thin tree branch
When male cicadas are infected with Massospora, they exhibit both male and female mating behavior: singing to attract females and flicking their wings to attract males. Nature Picture Library / Alamy Stock Photo

Cicadas are a sex-crazed species. Males sing the song of summer at the same volume as a lawnmower to attract mates, as residents of the mid-Atlantic and midwestern United States will experience this year with the emergence of Brood X.

But a fungus called Massospora can take it up a notch, Karen Zamora reports for NPR. This white, chalky fungus infects about five percent of cicadas. It takes over their bodies and produces cathinone, an amphetamine, that makes the bugs mate even more. Massospora sticks out of the bug's back instead of genitals, so every time the infected bug attempts to mate is an opportunity for the fungus to spread.

"This is stranger than fiction," says West Virginia University mycologist Matt Kasson to NPR. "To have something that's being manipulated by a fungus, to be hypersexual and to have prolonged stamina and just mate like crazy."

Massospora fungus lurks in the soil until the cicadas emerge from the ground, Kasson tells Coral Murphy Marcos at the Guardian. When the cicada nymphs emerge from underground, some ingest the fungus, and the fungus is activated by a hormone from the cicada. Once inside, the Massospora consumes the inside of the cicada and grows until it cracks through the bug’s exoskeleton. Their genitals fall off and get replaced by a big white ball of spores.

The fungus has a special effect on male cicadas. Massospora-filled males continue to sing to attract female mates, but they also perform the same wing-flicking that females do to males to signal they’re ready to mate. Without genitals, none of their attempts to pair up will result in offspring.

“It’s this gender-bending, death-zombie fungus,” says John Lill, who studies cicadas at George Washington University, to Jon Webb at the Evansville Courier & Press. “Really what they’re doing is spreading these spores all over the place.”

Different species of cicadas get different drug-laced responses from Massospora infections. While periodical cicadas—like the dark brown, red-eyed Brood X—get a boost from the stimulant cathinone, annual cicadas wind up full of psilocybin, the same chemical found in psychedelic mushrooms.

Although some people eat healthy cicadas, experts do not recommend eating the cicadas for the fungus and its drugs. For one thing, Kasson tells the Guardian, the cathinone and psilocybin are just two of a thousand compounds that they found in the fungus-infected cicadas. For another, most people who eat cicadas tend to harvest those that have recently molted. (Entomologists described them as tasting buttery and nutty like asparagus to Mark Kennedy at the Associated Press.)

Fully grown cicadas would be crunchy and unpleasant, per the Courier & Press. Even cicada predators, like squirrels and birds, avoid the Massospora-infected insects.

While Massospora’s cicada-zombie strategy was discovered the 19th century, researchers didn’t discover that they produce drugs until very recently, Ed Yong reported for the Atlantic in 2018. The drugs may explain why the infected cicadas have the time of their lives, despite their unfortunate circumstances.

“If I had a limb amputated, I probably wouldn’t have a lot of pep in my step,” said Kasson to the Atlantic. “But these cicadas do. Something is giving them a bit more energy. The amphetamine could explain that.”

Get the latest stories in your inbox every weekday.