Brood X Cicadas
The Watoga Trail Report is starting a new series about the anomalies and mysteries found in nature. This will be the first installment of What In The World? and it is my hope that you will find these stories bizarre, sometimes shocking, but always interesting.
(Readers, please be advised that the following article contains the liberal use of anthropomorphisms. * If you find this insulting to your sense of scientific integrity, my dog, Bongo, and I offer you our sincerest apologies.
My other dog, Daisy, declined to apologize on the basis that she feels no need to mollify the fragile human ego. That is her opinion, not mine.)
Meet Magicicada, the victim in this story.
West Virginia is either blessed or cursed, depending upon how you feel about the hordes of loud insects that are about to invade us, at least in the Eastern Panhandle.
Don’t look to the skies; these guys are coming from the underworld.
Last June we had an event here in Pocahontas County in which billions of Magicicada, the genus of red-eyed cicadas called Brood IX (9), made their appearance after a 17-year hiatus.
The Watoga Trail Report took a deep dive into the lifecycle of the periodical cicadas. We also discussed their mating rituals in which the males sing to their pro-spective mates and the females answer the serenade with a flicking of their wings.
We focused on the beauty of this ephemeral experience rather than merely dwelling on the technical aspects.
I had experiences with cicadas here for a month or more, that fostered a greater appreciation for these creatures.
I remember being out in the faint light of early morning, watching a ghostly white nymph slowly work her way out of her bronze-hued shell. Her large red eyes seemed fixed on me as she sent liquid into her wings, miraculously expanding them into iridescent pinions right before my very eyes.
On another occasion, a cicada perched on the tip of a finger where he seemed quite content to visit for a spell. I decided to snap my fingers with the other hand to see how he responded to a sound that mimics the flicking of a female’s wings. He immediately launched into song, confirming that he was indeed a male, and creating a sense of connection with this beautiful insect.
The article discussed how the newly hatched larvae drop from the trees and immediately begin burrowing their way deep into the ground where they seek out tree roots for sustenance.
In total darkness, these delicate insects grow and transform into nymphs. They wait for years until nature’s ancient clock signals them that it’s time to burrow their way up to the world of light.
But there is something sinister waiting for many of them as they make their way to the surface – a flesh-eating and mind-controlling fungus.
So, a quick (and simplified) review of the cicada life cycle is in order here before we take a peek at the butt-munching fungus whose only function in life is to turn these unsuspecting insects into zombies:
1. After emerging from the ground after either 13 or 17 years, the nymphs climb up on trees and break out of their shells as adults, leaving behind the empty exoskeletons.
2. The males start up their daily chorus to attract females, and the females answer by flicking their wings. Once they find each other, they attend to the task of mating.
3. The pregnant females, who mate only once, deposit their eggs in incisions they make on tree branches.
4. After mating, most males set about dying, while a smaller percentage continue their symphony of love and desire in hopes of another rendezvous or two before biting the dust.
5. After hatching, the cicada larvae drop off the branch and onto the ground where they burrow down some four to six feet below the surface. Here they feed on xylem fluid from tree roots and continue to grow and develop.
6. On a sap-related cue, the newly molted nymphs return to the surface to repeat the cycle of life.
But, there is another element of their life that is so macabre that it is rarely mentioned in literature about these fascinating and beautiful insects.
Meet Massospora the villain in this story.
Massospora is the genus of the fungus, but our concern in this story is the specific species of the genus. And the species that brings death and destruction to periodical cicadas is M. cicadina.
M. cicadina is a fungal pathogen, meaning that it can cause diseases in humans, animals, insects and plants. This particular fungal pathogen targets only the 13- and 17-year periodical cicadas.
The way M. cicadina initially attacks the cicada is by attaching itself to the nymph as it burrows up to the surface and promptly eats its way into its abdomen.
(The burrowing is triggered by a surface soil temperature of 64 degrees Fahrenheit. This temperature may also be responsible for alerting the fungus that the cicadas are on the move.)
Once in the abdomen of the unwitting cicada, the fungus sets about creating a home for its spore. And in order to do that it literally eats out the entire interior of the abdomen including the cicada’s genitalia.
This results in the sterilization of the cicada, whether male or female.
It’s at this point in the discussion, that many readers, if not appalled, are at least disgusted. But, please read on, it gets worse for our red-eyed friends! M. cicadina has a few more sadistic tricks up its slimy sleeve.
Not only are the cicadas infected with the fungal spores, but M. cicadina has also introduced a substance into the insects called cathinone. Cathinone is a chemical compound in the amphetamine family that stimulates the cicadas as well as making them – well, horny.
About this time, the fungus has munched away the terminal rings of the abdomen, causing it to detach from the body. The normal abdomen has now been replaced with a chalky-white plug of spores, anxious to infect other cicadas.
And the very next thing to happen is why the infected cicadas are often referred to as the “Flying salt shakers of death.”
Fueled by the cathinone, the hapless cicadas fly about the trees desperately searching for a mate, all the while spreading the virulent M. cicadina spores like salt from a shaker.
Our villain, M. Cicadina, has one more lethal curse to place on the defenseless periodical cicadas.
Those uninfected cicadas that made it through the burrowing and mating process unscathed, may become infected by contact with the spore – bearing zombies discussed above.
But, with this second stage of infection, the spores that form in the abdomens of cicadas are in a “resting” state and cannot infect other cicadas.
When these infected cicadas die, the dormant spores are released to the environment, many making their way into the ground. It is here that they wait until the next emergence of the periodical cicadas.