History and culture
Saurians were humanoid lizards with bulgy eyes and scaly skin. An individual's skin color could vary, including pink and grey, while possible eye color included black and orange/yellow. (Star Trek: The Motion Picture; DIS: "Brother")
The original Saurians were designed by Fred Phillips and Robert Fletcher for The Motion Picture. With the approval of Gene Roddenberry, the Saurians, as well as numerous other new species in the film, were named by Fletcher and provided a backstory by him. The following is a brief description, in Fletcher's own words:
"SAURIAN – A lizard person, very able, excellent space officers. Learned to communicate in Earth tongue, have complicated vocal language of own. Have upright, direct posture. Intelligent. Can breathe a number of gases. Valuable in exploration of new areas because of enormous strength due to four hearts. (Note: in rec deck scene only.)" (The Making of Star Trek: The Motion Picture, pp. 132-133; Starlog #33, April 1980, p. 71; Star Trek: The Magazine Volume 2, Issue 9, January 2002)
According to Star Trek: Star Charts ('United Federation of Planets I") and Stellar Cartography: The Starfleet Reference Library ("Federation Historical Highlights, 2161-2385"), there was a planet named "Sauria" in the star system Sauria (Psi Serpentis), which might possibly be the system of origin for this species, in the Alpha Quadrant. This was a trinary system with a trio of G-class stars. In 2378, Sauria was listed as a Federation member.