I believe the Rivieras were another one-hit-wonder act. There was a group in the Fifties called the Rivieras that charted with Count Every Star in 1958, but I don't think they're the same.
I like this version (the girls are frisky in old Frisco!):
You’re correct. The Rivieras who recorded “Moonlight Cocktails” and the Rivieras who recorded “California Sun” were two completely different groups. They were also of completely different races.