A reptile was a type of cold-blooded animal.
Dodo Chaplet pointed out a chameleon to Steven Taylor while they were aboard the Ark. (TV: The Ark)
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)