Unidentified Gall on Willow Leaf

[lrmalpas]

Can anyone help in identifying this gall on a willow leaf?

Goat or grey willow is the host I think. The leaf itself was dead and dry on the ground when I found it, and I only found one specimen. Found in fen carr wet woodland in Norfolk.

My initial thought was that it looked like a Red Pea gall (Cynips divisa) or Currant gall (Andricus quercusbaccarum) found on oak, but I thought these were oak specific...

It looks like an invertebrate could be the agent, although I can see no larval/adult exit holes.

Thanks,

[Merrow]

Oooh I found these on our willow tree leaves this year - dozens and dozens of them -- see www.growveg.info GYO Gardening, Allotment and Wildlife Forums • View topic - Willow Galls? (apologies for the external link but I don't have the photos any more on the computer)

I'll be watching this thread with interest as I never got an id on mine.