Reptile
A reptile was a type of cold-blooded animal.
On Earth
During the 2150s Dalek invasion of Earth, many animals escaped from zoos during the plague. Most of them died, but reptiles such as alligators thrived in the London sewers. (TV: The Dalek Invasion of Earth)
Dodo Chaplet pointed out a chameleon to Steven Taylor while they were aboard the Ark. (TV: The Ark)
One of the terms that Silurians referred to themselves as was "Earth Reptile". (PROSE: The Scales of Injustice) By the time of the Earth Empire this term had expanded to include the Sea Devils. (PROSE: Love and War) Both of these species were classified as homo reptilia. (COMIC: Clara Oswald and the School of Death) "Reptile" could also be used as an insult against the species. (TV: The Name of the Doctor)
Elsewhere
The Cynrog were reptilian humanoids who hid behind masks and worshipped the chaos god Balor. (PROSE: The Nightmare of Black Island)
The Re'nar were intelligent lizard-like reptiles from the Matrua Nebula that were at war with the Ju'wes. (COMIC: Ripper's Curse)
Historians who studied the Dalek race believed that, like on Earth, the dominant lifeform on prehistoric Skaro had been large reptilian creatures. (PROSE: Dalek: The Astounding Untold History of the Greatest Enemies of the Universe)
The native species of the planet Destination, the Dalmari, were a reptilian species. (AUDIO: The Destination Wars)