Eutermesan

Eutermesans were a humanoid species native to Zone Eutermes. One Eutermesan, C'rizz, became the Eighth Doctor's companion after meeting him while on the run from the Kromon. (AUDIO: The Creed of the Kromon)

Biology
The Eutermesans were a race of exoskeletal reptilian humanoids, with vestigial bone structures on their heads. They also had the ability to change their skin colour like chameleons, blending with their surroundings. (AUDIO: The Creed of the Kromon)

Eutermesans were emotional and mental chameleons as well. They were able to shape their personalities to those around them, which also made them susceptible to manipulation. (AUDIO: Terror Firma)

The eyes of Eutermesans worked differently from those of other humanoids. C'rizz claimed that he could see Charley Pollard's skeleton if he stared hard enough. (AUDIO: The Natural History of Fear)

Eutermesan hearing was significantly better than that of humans. (AUDIO: Caerdroia)

Culture
The Eutermesans were the slave force of another race, the termite-like Kromon, and were mostly farmers. At induction, Eutermesans were divided into castes, some into management, some into food production and some into research workshops. (AUDIO: The Creed of the Kromon)

They had a saying: "Everything changes but nothing's truly lost." (AUDIO: The Twilight Kingdom)