Fantastic, I was hoping you would play too :lol:
My theory is that I have an Ancistrus triradiatus.
It does not look like a cirrhosus at all. having said that there are soooo many different types of bn's that it is completely possible that that just have not gone through the entire list of possibilities.
the guy i have is about 3-4 years old, small for that age, but has nice bristles and a plain brown colour, like a bark. Not a single spot on him.
I also had a mega huge one a while ago who was easily 18cm or more which I don't think is really normal for them.