- This article is about the character. For the novel by Sasya Fox, see THETA.
Theta is a character created by Mark Merlino in the late 1970s, noteworthy as the first example of Merlino's skiltaire species of weasel-like aliens. She is a grey female arboreal skiltaire with a blue dorsal stripe and green eyes. Theta became a logo-character for her creator, appeared in many science fiction fanzines and APAs, on event posters at science fiction and comic conventions, and commissioned art.
Theta was rescued by a human biologist and eventually became his companion.