Original: The earliest gharial may have been related to the modern types: some died out at the same time as the dinosaurs (at the end of the Cretaceous), others survived until the early Eocene.
Simplified: The earliest Gavialoidea may or may not have been related to the modern types: some died out at the same time as the dinosaurs (at the end of the Cretaceous), others survived until the early Eocene (about 35 million years ago).