Freshwater Jellyfish

Freshwater Jellyfish, as it is called, aren't really from the freshwaters.
I quote "Is there such a thing as a true freshwater jellyfish? No, not really, but there is a species that looks like a jellyfish, reproduces like a jellyfish and is known under the common name freshwater jellyfish: Craspedacusta sowerbyi. This species is distinguished from true jellyfish by a structure called a velum that freshwater jellyfish has and marine jellyfish lacks. However, most people still look at Craspedacusta sowerbyi as a jellyfish and I will henceforth just refer to it as freshwater jellyfish."