Escudo?

Well as some of you may notice in some of my threads earlier Im setting up a 166 gallon viv for pumilio and I'd love to put a pair or better a trio of escudo's in it, and Id like to know a bit about them since I cant find much on google. How large to they get I know they are the smaller ones of the pumilio. What do you guys use in there environment ect. and a price range for a pair or trio would be nice. Thanks