No, it's not a monte dourado, I don't have any that are that small, the two of mine are adult (the one in the background is a monte dourado in the 2nd pic). Not an L066 or L333 either. It's only a trick question if you don't know the answer 
WyldFya;946950; said:Tough one, looks to be a Hypancistrus sp. 'Monte Dourado'.