Pennsylvanians cannot stomp their feet fast enough.

They are trying. But no matter how many spotted lanternflies they crush underfoot, they cannot seem to keep the hordes of the invasive insect from flapping in their faces, sucking nutrients from valuable vineyards and lurking in their nightmares. Even after death, they pester commuters when their carcasses crunch underfoot on city sidewalks.

The inch-long creatures, which look a bit like moths and hide scarlet wings beneath gray spotted ones, moved into Philadelphia in recent weeks, swarming around parks and skyscrapers and drawing a clear response from officials: “Kill it!” a state website blares by way of advice to residents who encounter the flies. “Squash it, smash it … just get rid of it.”

In response to the insect infiltration, the Pennsylvania Department of Agriculture has quarantined 14 counties — regulating what can be taken in and out — and has set up a portal and a hotline (1-888-4BADFLY) to report sightings of the species, which is native to parts of Asia.