Khorlthochloi
From Tardis Wiki, the free Doctor Who reference
The Khorlthochloi were an ancient race of aliens who went extinct around a billion years ago. They were one of the first races to attack Earth, but were somehow stopped. Much later, in 5720, after World War Six, Human archaeologists discovered the ancient remains of a spaceship, though they never found out about the owners. (DW: Synthespians™)