While I have no idea of the diagnostic characteristics of a Baryancistrus spp. and unfortunately haven't taken any shots of my fish yet, my fish are shaped very much like the fish pictured here:
http://www.planetcatfish.com/catelog/lo ... /656_1.htm
With a strongly forward top leading edge to the caudal fin, with a curved shape (as pictured) not really forked.
The closest shot I have seen is Ingo Seidel's shot of L-19 in the Cat-ELog. Which BTW is also listed as a Baryancistrus. The fish in Ingo's shot looks very much like a juvenile of my fish. The pattern is not quite as distinct and is a bit more complex on my fish(stress coloration is much clearer though). The eyes in my fish are also much smaller (it is typical for young fish to have larger eyes by proportion).
Your pictures listed as L-122 are also close... How large were the fish in these pictures? Mine are still about 2.0" Std. length.
OK, you've inspired me, I am off with the cameras for some shots... Digitals possibly tonight, no promises on quality though... Slides in two weeks.
Sincerely,
Paul E. Turley