Xiphonactis

The xiphonactises are the secondary antagonists of Journey to the Center of the Earth.

History
When the characters crossed the underground ocean, they were attacked by an army of xiphonactis. They began batting them away with various appliences. After a long fight against the predatory fish, they were saved when a herd of aquatic tanystropheus rushed up from the sea and voraciously decimated the dinosaur's fish minions.