A recently discovered box jellyfish species living in near Singapore looks nearly identical to another jellyfish previously discovered by the same scientist. But regardless of whether or not you can tell Chironex blakangmati and Chironex yamaguchii apart, you’ll want to steer clear of both of them. Box jellyfish didn’t earn their “sea-wasp” nickname for yellow-and-black stripes.

Cheryl Ames, a marine biologist at Japan’s Tohoku University, collected C. blakangmati during an expedition near the coast of Singapore’s Sentosa Island. The team initially assumed the invertebrate was an example of C. yamaguchii, but later genomic testing revealed something else entirely.

“We realized they were completely distinct,” Ames explained in a statement. “I actually went back to dust off an old sample of C. yamaguchii I still had in storage in Okinawa to help with the comparisons.”

Apart from genetics, the key difference setting C. blakangmati apart from its three known Chironex relatives is its perradial lappets. This anatomical feature on the bottom of the box jellyfish’s bell-shaped body strengthens the pulsating musculature that propels it through the water. Other Chironex species include pointy canals at the tips of their perradial lappets, but C. blakangmati notably does not.

Canals or not, they are remarkable creatures. The vast majority of jellyfish don’t rely on vision and passively float in ocean currents, but members of the Chironex genus do not. Instead, they have evolved complex eye organs that help them locate prey. They then use that same musculature supported by the perradial lappets to actively swim through the water towards its target.

In this sense, C. blakangmati certainly lives up to its scientific name. Sentosa may be Malay for “peace and tranquility,” but the island once called something very different. Historically, it is also known as Pulau Klakang Mati, which translates to the “Island of Death from Behind.”