The cicadas of Brood II are starting to emerge. For the past 17 years they’ve been hiding, buried underground across the northeastern United States, waiting for this moment. But something has been waiting for them. Something dangerous. A killer, evolved to sit idly by while the larval cicadas grow underground and to strike just when they crawl to the surface.
This little white fungus eats the cicada alive until nothing is left in its abdomen but spores. Then it ruptures the tissues holding the abdomen together, breaking the end off, and thereby turning the still-alive-and-flying cicada into a salt shaker of death for others below.
The spores, falling from the sky from the guts of ruptured cicadas, go on to infect insects still crawling around on the ground below.
This first group of cicadas, infected in their tunnels, will die during the time they’d normally mate, while producing spores than can directly infect other cicadas. But the second group of cicadas—those infected on the wing—will die filled with thick-walled resting spores. Resting spores are entrusted with the long wait in the soil til the next generation emerges, a year or perhaps 17 years down the road.
The Massospora fungus is found wherever cicadas thrive, says Macias. No one is really sure how the fungus evolved to patiently wait out the cicadas and their staggeringly-long lifecycle.
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