The Pralor homeworld was an inhabited planet in the Delta Quadrant and the homeworld of the Pralor, which were driven to extinction by Automated Personnel Units some time before 2372. (VOY: "Prototype")
This planet was only mentioned in dialogue.
According to Star Trek: Star Charts (p. 84), there was a star system named Pralor, which might possibly be where this planet was located in, in the quadrant. This was a trinary system with a G-class star, a M-class star, and a K-class star. The USS Voyager visited this system on stardate 49240.