Dorsal has more than 10 rays, that makes him a Pterygoplichthys species. Took a look through the genus at PlanetCatfish, though, and didn't see anything that was a perfect match. You might want to look there yourself, as you are more familiar with all the color phases of your fish; you could find a match.
Some of these get quite large, but a couple of species stay under a foot.
Ugh...I don't know why I came back to this post. I have spent hours on planet catfish looking at plecos because it didn't look like a common to me, Chrome just had me go back and look again. (It was actually very interesting but also very frustrating) I'm certain you have a pleco. That is all I am certain about. Good luck.
I tracked the thread back to this image calling it a "chocolate albino". its obviously not a true albino but is a leucistic fish like the blue eyed lemon bushynose pleco. I'm not entirely sure if I'm correct but this is the only specific guess so far.