A black and yellow striped wasp mimic formerly called C. cultratus. This species of stem boring sawfly is very similar to Cephus pygmeus and detailed examination is needed to separate the two species.

Very similar to Cephus pygmeus but this species has a mainly dark hind tibia (often with just a yellow strip along one side).

• Less swollen antennal club (pre-apical segments NOT broader than long)
• Hind tibia yellow with at most the apex ringed darker
• Sawsheath protrudes at a downward angle to body profile (viewed side-on)
• Claws with an erect inner tooth, not parallel to the end tooth

A specimen must be keyed with a microscope. Please describe how you reached an identification.

Can be seen on a variety of flowers and other vegetation.

Spring and summer.

This is a stem boring sawfly, the larvae living in the stems of mushrooms etc.

Fairly common and widespread in England and Wales.

Fairly frequent in Leicestershire and Rutland.

https://www.sawflies.org.uk/cephus-spinipes/