ARS TECHNICA – A plague of parasitic mites has descended upon Illinois in the wake of this year’s historic crop of cicadas, leaving residents with raging rashes and incessant itching.
The mighty attack follows the overlapping emergence of the 17-year Brood XIII and the 13-year Brood XIX this past spring, a specific co-emergence that only occurs every 221 years.
The cacophonous boom in cicadas sparked an explosion of mites, which can feast on various insects, including the developing eggs of periodical cicadas.
But, when the mites’ food source fizzles out, the mites bite any humans in their midst in hopes of finding their next meal. While the mites cannot live on humans, their biting leads to scratching. The mite, Pyemotes herfsi, is aptly dubbed the “itch mite.”
“You can’t see them, you can’t feel them, they’re always here,” Jennifer Rydzewski, an ecologist for the Forest Preserve District of DuPage County, told Chicago outlet The Daily Herald. “But because of the cicadas, they have a food source [and] their population has exploded.”
The mites are around 0.2 millimeters in length and very difficult to see with the naked eye, according to agriculture experts at Pennsylvania State University. They have four pairs of legs and are tan with a reddish tinge.
Female itch mites can produce up to 250 offspring, which emerge from her abdomen as adults. Emerged adult offspring quickly mate, with the males then dying off and the newly fertilized females dispersing to find their own food source.
Itchy outbreak
Besides “itch mites” these parasites have also been called the “oak leaf itch mite” or “oak leaf gall mite,” because they have often been found feasting on the larvae of oak gall midges. These midges are a type of fly that lays eggs on oak trees …
“Great fleas have little fleas …”
HEADLINE HEALTH – This bug-eat-bug story calls to mind a favorite poem by British mathematician Augustus De Morgan (1806 – 1871):
