Re: Have we ever seen subspecies in Trek?
During TOS, the make up on the actors portraying Klingons varied from episode to episode. In-unverse this could be explained as races within the basic Klingon species.
The planet Cheron, had (at least) two. One black/white, the other white/black.
Every time the Federation Council is featured in the new series, it should be like a episode of House of Cards, with some Throne of Swords thrown in too