could it be a different gold nugget L177 - Gold Nugget Pleco 'Large Spot' (from the Rio Iriri), L081 - Gold Nugget Pleco 'Small Spot' (from the Rio Xingu), or the commonist L018 - Gold Nugget Pleco 'Medium Spot' (from the Rio Xingu). There are also tonnes of black with white spot plecos out there so could be another type...
