Scientists need your help to find cicadas infected with zombies and filled with intestinal pudding


If you’re in the mood for a weird scavenger hunt this spring, you’re in luck. Entomologists are asking the public to report any sightings of adult cicadas infested with the parasite. Cicadin Massospora, also known as zombie cicada mushroom. Those watching will have a simple clue: the abdomens of infested cicadas are regularly filled with a pudding-like fungal plug that can eventually cause their buttocks and genitals to droop.

There are many sinister parasites in the world, but Mr. cicada is certainly one custom made for a horror film. It infests certain species of cicadas in the Magical genus that has much longer life cycles than others – what is called periodical cicadas of North America that only emerge en masse from the ground every 13 or 17 years at a time, usually between late April and early June. During their brief weeks of life on the surface, these cicadas mate and lay the next generation of eggs which hatch and burrow into the ground, beginning the process again. Periodical cicadas are grouped into broods, based on their expected arrival, although broods are made up of several species.

This year is a particularly unique cicada season, as two broods (of 15 currently active) have emerged: the 17-year-old brood XIII, concentrated in northern Illinois, and the 13-year-old brood XIX, which will be much more widespread throughout the country. the southeastern United States. The arrival of these cicadas also means that Mr. cicada will make a rare appearance above ground, providing an exciting opportunity for scientists like Matthew Kasson, a professor of forest pathology and mycology at West Virginia University.

“Our fungus is what they call an obligate biotroph, which means it needs a cicada host to survive. You can’t raise them in the lab, because you can’t raise 17-year-old cicadas in the lab,” Kasson told Gizmodo by phone. “So we rely exclusively on harvesting the fungal plugs on the back of infected cicadas that are collected during outbreaks. And it’s essential that we collect as many as possible.

A cicada infected with the fungus Massospora cicadina.
Photo: Matthew Kasson

Like their hosts, Mr. cicada has a complicated life cycle, filled with sex and drugs. Some cicadas become infected with the spore form of the fungus when they begin to burrow out of the ground as adults. These cicadas develop a specific type of infection classified as stage I. Cicadas infected at stage I will appear normal at first, but after about a week, their lower abdomen – including genitals – begins to tear off, having been replaced by a mass of whitish mushrooms. fabric. Fungal plugs are loaded with spores that can infect healthy cicadas.

Males are more likely than females to completely lose their abdomen and waste, but that doesn’t stop them from trying to mate, and that’s when things get even stranger. Although both sexes get stage I infections that they can transmit to others, infected males will try to have sex with any cicada in the area. In addition to making the usual male mating call, some infected also begin to behave like females, stealing their mating ritual of flapping their wings to entice healthy males to court them to no avail. These frenzied orgies don’t help the cicadas, but they fuel the continued spread of the parasite.

A cicada infected with the fungus Massospora cicadina.
Photo: Matthew Kasson

Scientists still don’t know exactly how the fungus so radically distorts cicadas’ behavior, but several years ago Kasson and his colleagues do a key discovery. Once inside a host, Mr. cicada appears to produce large amounts of cathinone, a type of stimulant, which likely plays a large role in keeping cicadas driven to mate while ignoring any other distractions, such as a missing cigarette butt. They also found that other Massospora species that infect annual cicadas can produce psilocybin, the main ingredient in psychedelic mushrooms.

But there’s still so much we don’t know about when it comes to these sneaky parasites — mysteries that will require lots of samples for researchers like Kasson to examine.

There is a second stage of Mr. cicada infection, for example. These stage II infections still hollow out the cicadas’ abdomen but will now produce resting spores with thicker walls (Kasson describes these fungal plugs as resembling a “creamy pudding”). Stage II male cicadas also no longer turn into pansexual horndogs. The resting spores are not intended to infect adult cicadas, but are time bombs that seed the soil and wait to infect the next generation of nymphs unlucky enough to encounter them 13 to 17 years later.

Stage II infections are acquired from adult cicadas infected at Stage I and tend to appear later in the season. But according to Kasson, the exact details of how infections transition from stage I to stage II are still unclear. It is unclear whether adult cicadas can catch stage I infections from other infected adults if caught early enough in the season, for example, or whether a stage I infection will always cause a stage II infection.

Another lingering question concerns cicada broods. The team’s previous analysis found evidence that the Mr. cicada parasites infecting 13-year-old cicadas are slightly different genetically from Mr. cicada infecting 17-year-old cicadas. This leaves open the possibility that these two groups of parasites are actually two different species. But because there are far fewer 13-year-old broods today (only three out of 15), Kasson’s team has until now only had limited samples to work with. The next brood of 13 years after this one won’t arrive until 2027, so researchers hope to catch as many cicadas as possible before the end of the season.

“We really need to be opportunistic and take advantage of these emergences when we can,” Kasson noted.

In recent weeks, Kasson has made a to call to the public via social networks. The request is quite simple: people who encounter possibly infected cicadas must photograph them and upload their photos, either iNaturalist or the most specific CicadaSafari. They can also get in touch with Kasson directly through his X/Twitter handle. @imperfectfunguy. Although Kasson’s team is very keen to collect real specimens, no sighting is too small.

One thing you shouldn’t do if you see a cicada infected with fungus is try to eat its intestinal pudding – a real possibility that Kasson had to warn overly curious people against, especially those interested in stimulants found inside.

“The cathinone we found in cicadas was just one of 1,000 different compounds we found that were specifically linked to the fungus. And if you eat the caps, you might find mycotoxins, bacteria, nematodes or other microbes that could be very harmful to you,” he said. “So I would say it’s probably not worth it.”



Leave a Reply

Your email address will not be published. Required fields are marked *