I'm don't know the morph you name, but I remember the original yellow backs that came in in the late 1980's. They were called Mont Bufo Mort (Dead Cow Mountain) for the locality they were found. They were a larger frog as I remember and some were the most intense yellow you ever saw. There is a picture in one of the later ISSD Bulletins. Beautiful frogs. I don't know if this will help, but it can't hurt.