Basilosaurus ("king lizard") is a genus of early whale that lived 40 to 34 million years ago in the late Eocene. The first fossil of B. cetoides was discovered in the United States and was initially believed to be some sort of reptile, hence the suffix -"saurus", but it was later found to be a marine mammal. Richard Owen wished to rename the creature Zeuglodon ("yoked tooth"), but, per taxonomic rules, the creature's first name remained permanent. Fossils of B.