Cuvierina atlantica is a species of sea mollusk, commonly known as a sea-angel pteropod.
[1] This species occurs in the North Atlantic Ocean.
The gastropod has small flaps it uses to swim, as well as a cylindrical shell for protection.
Cuvierina atlantica are able to generate thrust on two occasions during each wingbeat cycle, in comparison with sea butterflies that swim like flapping insects, which only generate thrust once.
[2]