Now I am puzzled. That reference quite clearly shows that Blonde "Rays" are really skate........
For example a RAY tail is described as follows :-
"tail relatively slender to whip-like, usually with a saw-edged stinging spine midway along its length "
whereas a SKATE tail is
"tail relatively stocky, without a stinging spine "
Now looking at your picture and the way you are holding your fish - tell me where the stinging spine is ( in your hand maybe ! ) and the way that the tail is "whip like" ?
Common name is Blonde Ray but it is really a skate ( as is a Thornback ) - and the article referenced says exactly that.
I quote :- "The problem is made more difficult by the fact that many of the species around the UK coastline are misnamed. For example, the thornback ray is actually a skate!"
PS: Any chance of a picture of the Undulate Ray, just so I can be sure it is not a Thornback ?