A large lemon-yellow and black sawfly. Very similar to T. arcuata and T. brevicornis. The species are very difficult to separate without detailed examination. Where the image has not received expert verification, which is necessary to be certain of accuracy in this species, it is highlighted with a red box. For that reason it is only claimed as likely to be this species. Images taken at the end of August would suggest that the species is unlikely to be T. arcuata which flies quite early.
Adult takes small insects and visits umbellifers for pollen and nectar
When to see it
From June to September… NatureSpot