Scaled Ones are first introduced in Three Against the Witch World.
Appearance: Scaled ones look like jewel-scaled or rainbow-scaled lizard whose front feet work as hands. In Trey of Swords Tsali is mentioned as having a crest and capable of both two-legged and four-legged movement. Their heads are larger and more rounded than a normal lizard's to accommodate a larger brain.
Life Span: It's unknown how long they live. They could have a fairly long lifespan, however.
Power: Scaled Ones can communicate telepathically, what else they can do is largely unmentioned.1
Other: Scaled Ones seem to serve as sentries to the Valley of Green Silences. It's mentioned in Three Against the Witch World that they are led by a chieftain. Crytha in Trey of Swords thinks of Tsali as a "Lizard man" and his people as "Lizard folk" which may also be an appropriate name for their race. It's possible they also live in the Were-Riders' forest in the Waste as Kerovan catches glimpses of lizard type creatures there (in Gryphon in Glory) who seem to act as sentries for the Weres.