What is "clione"

Clione \Cli*o"ne\, n. A genus of naked pteropods. One species ( Clione papilonacea), abundant in the Arctic Ocean, constitutes a part of the food of the Greenland whale. It is sometimes incorrectly called Clio.

Clione is a genus of small floating sea slugs, pelagic marine gastropod mollusks in the family Clionidae, the sea angels.

Clione is the type genus of the family Clionidae.