Terrapratch

Terrapratches were giant turtles which moved in space. They could live in the breathable atmosphere that surrounded their shells. The Eleventh Doctor, Amy Pond and Rory Williams encountered a race of unwitting parasites which had unknowingly been living on a fatty, white substance beneath one Terrapratch's shell. The Terrapratch grew weaker and endured great pain, causing disruptive and frightening earthquakes believed to be the work of Sky Goblins. The Doctor encouraged a happier co-existence by using photographs taken from the TARDIS whilst hovering above their worlds. (COMIC: The Parasites)

Behind the scenes

 * The turtles are similar to the Great A'Tuin from Terry Pratchett's series. Terrapratch is a portmanteau of terrapin and Terry Pratchett.
 * Similar space turtles appear in the comic stories Untitled and Epilogopolis.