Judas tree under attack

I haven't seen any insect lurking but what may be the most likely candidate that is scoffing my Judas tree? Any help would be welcome.

 

I have had my Cercis siliquastrum for many years and not encountered any problems. Even mine loses its leaves in the winter, flowers then develops new leaves. Mine is now leafing. It appears yours is budding so maybe your leaves are just dropping.

As I can't answer your question, perhaps this helps ...

Judas Tree & Its Diseases

 

Just guessing, but looking at the curled leaves I'd suggest some kind of aphid, they attack the softest growth, and stop the leaves from forming properly.
Are there a lot of ants on the tree?

 

thanks pete. I have given it the provado treatment to cover the wriggly option