Wikipedia
Melibe
Melibe is a genus of sea slugs, nudibranchs, marine gastropod mollusks in the family Tethydidae.
Most nudibranchs are carnivores, but their prey is usually sessile or slow-moving animals such as sponges or bryozoans. In contrast, Melibe is an active predator which traps fast-moving free-swimming animals such as small crustaceans, using its extendable oral hood. 1