i can be your angle....or yuor devil
Sea Angels are beautiful little shelless snails. They're clear with a light glow, bouncing as they flap their wings. It's no wonder how they got their name. They look like the sweetest little things! Their sole purpose on this planet is to consume the flesh of their cousins.
Sea Angels eat mainly, if not only, Sea Butterflies. You can read in depth about Sea Butterflies here. Just like their prey, their "wings" are a single modified snail foot. Inside that cute bulbous head is a striking set of tentacled mouth parts.
They use these tentacles, sometimes equipped with barbs or suction cups, to hold onto or reach into the victim snail's shell and slowly separate and pull them out. They can catch and eat a sea butterfly in 2 minutes! They're about twice as fast as their prey and they're active hunters, even hunting while mating!
They mate while ballroom dancing! Two lights spinning in the ocean, they can spend 4 hours joined together. Being a little known invertebrate, there's conflicting information on if they're protandrous or simultaneous hermaphrodites. Regardless, in their lives they will be male and female at some point.
As far as their role in the ecosystem, they're nearly as much victims as their prey. They're found where sea butterflies are found, they're eaten by what eats sea butterflies, and the environmental pressures act on them the same. Their main source of food is imperiled by ocean acidification. Being higher, if only slightly, on the food chain; the sea angels would go extinct from distruptions in sea butterfly populations first.
Sea angels are highly specialized and sucessful predators. They're very pretty and charismatic. However, they basically super-plankton maxing out at 2-3 inches in length. A whole suborder of creatures being dependent on another suborder in the same clade to survive is really cool and compelling, but I think that the dependent one is maybe the worse animal.