What is the answer to the crossword clue „the last of the three periods of the mesozoic era. it began 145.0 million years ago and ended 66 million years ago.“. We have found 1 Answers for: „the last of the three periods of the mesozoic era. it began 145.0 million years ago and ended 66 million years ago.“. Try to find some letters, so you can find your solution more easily.