What period during the mesozoic era did the coelophysis dinosaur live?

The Triceratops lived at the very end of the Cretaceous Period some 68 - 65.5 million years ago. To be more precise they lived in the Maastrictian Age the last stage in the Mesozoic Era. It only became extinct in the K-T extinction event that saw the death of all non-avian dinosaurs.