Real World article(written from a Production point of view)
According to the script for "Evolution", Beldoron was an inhabited planet with a consulate.
According to an unauthorized biography of Doctor Paul Stubbs, this doctor had an affair with the consul's wife. The doctor denied the affair saying that he was a good friend of hers.
The lines in which the planet were mentioned were deleted from the final episode. The scene in which these lines were said can be seen at TrekCore.