Fettuccine and Shrimp with Crustacean Cream Sauce

Scampi are crayfish-like saltwater crustaceans, not the shrimp that are usually served as a substitute in the United States. The correct English name for scampi is “lobsterettes,” but most of the time the French name, langoustines, is used instead. Although some langoustines are imported into the United States (mostly from New Zealand), they are difficult to find. Shrimp, crayfish, and lobster can all be substituted. This sauce is made with crustac