A Darkling Sea by James Cambias is a story of first contact between humanity and a seemingly primitive race of intelligent crustaceans living in the world ocean of a Europa-like moon. Europa’s fascinated me ever since I read 2010: Odyssey Two by Arthur C. Clarke, and that fascination as only grown as we’ve learned more about the ice-covered world.
Related movies and books: The Deep Range by Arthur C. Clarke (novel). The Europa Report (movie). The Abyss (movie).