Figwort Sawfly (Tenthredo scrophulariae)

This looks like a shiny kind of wasp taking a rest in the veg plot, but after some book-work I reckon it's a Figwort Sawfly (#278). Working out the identification is quite difficult as there are several other parasitic wasps and wasp mimicking nomad bees and hoverflies that look pretty similar. This sawfly’s larvae live on the figwort plant, while the adults hunt smaller insects.