Land of the Giants
started in '68, so it was a contemporary of Star Trek
, but Battlestar: Galactica
('78) was definitely afterwards.
In terms of roles for black women, they were certainly rarer in the '60s than roles for black men, but there were some of note. Most notable, of course, would be Diahann Carroll in the title role of Julia
('68). There was also Gail Fisher as Peggy Fair on Mannix
Nichelle Nichols as Uhura predates both of those, although she was never a regular (either contractually or in billing).
EDIT: Sir Rhosis
kindly informed me of East Side/West Side
('63) (which I've never seen), which co-starred Cicely Tyson in a much more prominent role than Nichelle Nichols ever had on the original series.