Brood X (pronounced 'Brood ten') was first noticed by physician Nathaniel Potter in 1783, who started documenting the 17-year emergence in 1817 and 1834 (Kritsky 2020). During the spring and summer of 2021, Brood X gained a lot of attention online as viral news items anticipated and reported on the emergence of trillion-member Brood X in eastern U.S. Where most cicada species have a 2-5 year life cycle, this particular species is periodical, meaning that they only emerge from below ground every 17 years (or 13 years for other Broods).
As pictured in the image, the cicadas crawl out of the earth and climb up the trees, where they cast-off their juvenile husks and turn into an adult. The males then start their famously loud mating calls, a sound made by muscle movement and a tymbal organ. After mating, the female cicadas lay hundreds of eggs each in tree barks. The cicadas die within a few weeks after emerging from underground and the newly hatched nymphs drop down and burry themselves for 17 years.
Among the many different Broods emerging periodically in the U.S., it is possible to see a cicada emergence nearly every year. It is therefore interesting to see this viral attention towards Brood X. News outlets across the world reported this year's biggest cicada event. The website "Cicada Merch" even sells Brood X t-shirts, mugs, ornaments, and baby rompers to celebrate the 2021 emergence.
Kritsky, G. (2020). Gideon B. Smith: America’s Forgotten Entomologist. American Entomologist, 66(4), 48–53. https://doi.org/10/gnpdk3