The Lobed Comb Jelly

(YouTube link)

This jellyfish has a better light show than the Disco Clam! The Monterey Bay Aquarium tells us a little about the lobed comb jelly:

Comb jellies are beautiful, oval-shaped animals with eight rows of tiny comblike plates that they beat to move themselves through the water. As they swim, the comb rows diffract light to produce a shimmering, rainbow effect. Voracious predators on other jellies, some can expand their stomachs to hold prey nearly half their own size.

Yep, disco cannibals. Which would make a great movie title or band name. Link  -via the Presurfer