Figwort Sawfly Tenthredo scrophulariae
There are a number of black-and-yellow Tenthredo species and most of them are very hard to identify. Luckily the Figwort Sawfly is the big exception. It is an unmistakable species, because of the all orange antennae. In most other species the antennae are at least partly blackish. Never try to identify these sawflies by studying the yellow on the abdomen. Some animals, like the one in the pictures, have broad yellow bands. One might even think the abdomen is all yellow. Others have very small bands, giving the impression of being almost entirely black. The Figwort Sawfly reaches a length of well over 10mm and is quite an impressive sawfly indeed.
The larvae live on Figwort and are quite striking: light greenish blue with a number of smaller and larger black dots. Like all sawfly larvae they are strict vegetarians. This does not apply to the adult animals. They are carnivores mainly, hunting small flies and other insects. This is a common species all over Europe.