do you mean so called sub species of GN's, or just how many are kept by MFKer's. Its been debated as to whether or not GN should have subspecies, although some coming from different rivers having slightly different characteristics:
L018 - Gold Nugget Pleco 'Medium Spot' (from the Rio Xingu)
L081 - Gold Nugget Pleco 'Small Spot' (from the Rio Xingu)
L085 - Adult L018 (Gold Nugget Pleco 'Medium Spot'): different number, because of different coloration
L177 - Gold Nugget Pleco 'Large Spot' (from the Rio Iriri)
(L018 and L085 is also said to be the same pleco, just at different ages.
I have a L018 and 177, but they both hide far to much for me to get a picture of anything but a tail, and are very nocturnal. but here are the different "types"... and a giant
(top to bottom: L085, L177, L018, L081, monster GN with Rio Xingu in background)
