The clione, a.k.a. sea angel, is a cute, translucent swimming sea slug that glides gracefully through icy ocean waters by flapping a pair of appendages that resemble tiny angel wings. Don't let the innocent, angelic look fool you, though -- the clione is a vicious demon come feeding time.
The Clione limacina species preys on its shelled cousin, the sea butterfly (Limacina helicina). When the hungry sea angel spots a suitable target, it lunges forward and rapidly unfurls a halo of six hooked tentacles from its head, locking its prey in a death grip. Slowly, the clione sucks the victim's body out of its shell, swallowing it whole.