[2] Cranchiid squid occur in surface and midwater depths of open oceans around the world.

Cranchiid squid spend much of their lives in partially sunlit shallow waters, where their transparency provides camouflage.

This buoyancy system is unique to the family and is the source of their common name "bathyscaphoid squid", after their resemblance to a bathyscaphe.

Often the only organ that is visible through the transparent tissues is a cigar-shaped digestive gland, which is the cephalopod equivalent of a mammalian liver.

This is usually held in a vertical position to reduce its silhouette and a light organ is sometimes present on the lower tip to further minimise its appearance in the water.