True percula is the common name for your standard amphiprion percula clownfish as opposed to amphiprion Ocellaris. Those are two common clowns that have been selectively bred to create certain "designer" strains. Many of the names can be specific to the breeder. Check out some of the big breeders' websites to see some of the varieties available. Some of the big ones are:
Oceans, reefs, & aquariums
Sustainable aquatics
Sea & reef