No, although one of the members (who actually died a few weeks ago -- Greg Magee) told my friend that there was a connection, but there's not a connection (there are no common members). They did evolve into Raw Umber on Virginia though, and one of the guys was the second drummer for the sons of slum. The twinight 45 actually did come out on another label as the mystics on orr, but that's even rarer than the mystiques.
I'm interviewing one of Mystique on Curtom on my show tomorrow, Fred Simon, who was also in the Lost Generation, I guess I will specifically ask him also during the interview.