The Clinging Jellyfish, officially dubbed the Gonionemus vertens, was collected last month by naturalist Naturalist Jesse Amesbury at Skimmer Tours during a trip in the Cape May area.
The jellyfish is difficult to see, growing to be only about an inch in diameter and mostly transparent, according to the NJDEP.
They have a "single distinctive" reddish-orange to yellow cross and between 60 and 80 alternating short and long tentacles containing the nematocysts, or stinging cells, the DEP says.
In other words, they'll hurt.
Experts at Salt Marsh Safari say the Clinging Jellyfish "isn't supposed to be in the Atlantic Ocean." They're native to the Pacific Ocean, but were introduced to Atlantic waters in the 1890s.
While the jellyfish aren't usually densely populated, they're highly sensitive to any disruptions and can quickly move to the surface, "potentially making contact with the offender," the DEP fact sheet says.
Dr. Paul Bologna, a marine biologist at Montclair State University, tells 6abc that swimmers should still take precautions, especially in the back bays or in "especially shallow water" brimming with vegetation.
Click here for more on the Clinging Jellyfish from the NJDEP.
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