The invasive Jorō spider has landed in Bucks County, Pa. Here’s what to know about the giant flying arachnid.

Despite rumors, sightings of giant flying Jorō spiders never materialized in New Jersey this summer. But they did land in Philly’s backyard.

On Sept. 5, a Jorō spider was found in Ivyland, a Bucks County borough nearly 30 miles north of Philadelphia, in the yard of someone’s home. The sighting was confirmed by a site visit from a local entomologist, according to the University of Georgia’s (UGA) Center for Invasive Species and Ecosystem Health. The center tracks invasive plant, insect, and wildlife sightings, including the Jorō spider, across the U.S. While there have been many sightings of spiders that look almost identical to the Jorō reported in Pennsylvania as early as June, this is the first to be confirmed.

“There were six individual spiders found in the same area, that turned out to be other spider species. Since these spiders [including the Jorō spider] were all found in the same location in Pennsylvania, it’s likely that they were accidentally brought to the area as eggs or a pregnant female spider on a vehicle, boat, camper, or other item,” said Pennsylvania State University arthropod identification expert Michael Skvarla. “If the spiders in the area are eliminated this year, that may be enough to eliminate them from Pennsylvania until they are accidentally introduced again at a later date.”

The bad news is that they’re here to stay in the U.S. after establishing themselves in Georgia in 2013, and scientists don’t know what kind of damage they will do. The good news is that Jorō spiders don’t pose a threat to humans or household pets, Skvarla said.

“They’re not very venomous at all, and they’re very reluctant biters,” he said. “Even if you pick them up, they might bite in defense if you grab one, but the fangs are so small that it’s hard for them to pierce human skin despite their large size.”

Jorōs, or Trichonephila clavata, are large brightly colored spiders that can fly using a technique called “kiting,” where a Jorō shoots silk webs into the air and uses them like balloons to travel.

“Based on previous estimates, Jorō spiders can move around 10 miles per year if they are unassisted. However, human-mediated movement can move them much further, much faster,” Skvarla said.

Female spiders are bright yellow and black, growing up to four inches (the common house spider is smaller than a quarter-inch), and spin webs up to 10 feet wide. Male spiders are smaller, brown-colored, and can’t spin webs. Females can lay a single egg sac containing 500 spider eggs.

In Japanese, jorō spiders are known as jorō-gumo, which translates to “entangling or binding bride,” according to Penn State Extension.

Jorōs will only attack if the spider feels attacked or provoked. A bite won’t lead to severe symptoms, unless a person is allergic to spider bites. Typically, a Jorō spider bite feels similar to the sting of a yellow jacket wasp, Skvarla said.

While it’s not yet known how Jorō spiders impact the ecosystem, they are native to China, India, Japan, North and South Korea, Taiwan, and Vietnam, and are considered invasive in the U.S. However, early observations by UGA scientists suggest that Jorōs can coexist with other orb-weaving spiders, sometimes even spinning a web close to or attached to another spider’s web.

Just like the spotted lanternfly, local residents should stomp or kill the Jorō spider when spotted, but not before taking pictures of the spider and reporting it to the Penn State Insect Identification Lab or UGA’s invasive species tracker.

“Since Jorō spiders are not native and not widely established here, the best course of action is to kill them when they’re found,” Skvarla said. “That said, there are important native spiders that may be mistaken for Jorō spiders, such as yellow garden spiders. So readers should verify the identity of any spider before killing it to avoid killing native species by mistake.”