I think Yepezi get the peppered look when full grown. Hard to really tell with the pic you have. I would some some form of yepezi. Pups would be really interesting with motoro mixed in.
Well maybe I shouldn't have posted the pics of them because now someone bought both rays from him. I just went and ahead picked up 2 females. Pics of them are on another thread. Some they they are yepezi some say humerosea. Whatever they are I am happy with them.