Berberis Sawfly larva

Berberis Sawfly larva

Observation - Berberis Sawfly larva. Description: Lots of these destroying the leaves on the Berberis! They seem rather inert and nearly all curled up so haven't been able to get a photo of one straight. The nearest I can find is Nematus ribesii but that does not appear to have the yellow spots on the

Lots of these destroying the leaves on the Berberis!
They seem rather inert and nearly all curled up so haven't been able to get a photo of one straight.
The nearest I can find is Nematus ribesii but that does not appear to have the yellow spots on the back.
As always grateful for an i.d. please