Historically it was confused with several Chrysaora species, resulting in incorrect reports of C. quinquecirrha from other parts of the Atlantic and other oceans.

[1][2] Most recently, C. chesapeakei of estuaries on the Atlantic coast of the United States, as well as the Gulf of Mexico, was only fully recognized as separate from C. quinquecirrha in 2017.

The Atlantic sea nettle is a bell-shaped invertebrate, usually semi-transparent and with small, white dots and reddish-brown stripes.

The sea nettle's sting is rated from "moderate" to "severe" and can be noxious to smaller prey; it is not, however, potent enough to cause human death, except by allergic reaction.

Sea nettles are also able to consume minnows, bay anchovy eggs, worms, and mosquito larvae.

Upon contact, the cnidocil will immediately initiate a process which ejects the venom-coated filament from its capsule and into the target.