Tleilax (also known as Tleilaxa or Tlulax) is the sole planet in the Thalim star system, and was home to the Bene Tleilax? - a society of genetically altered highly religious, and xenophobic humans.

Millennia later, the planet was called Tleilax and was known primarily for two things; Tleilax was the location of a renegade training center for Mentats, and was noted as the source of Twisted mentats. Tleilax was also the home of the Tleilaxu?, a race of humans composed of genetic scientists and Face Dancers.

A beautiful Earth-like world, with a nitrogen/oxygen atmosphere. It contained many areas of manicured terrain and vegetation.

On the net: Dune wikia,