One of two British Tenthredo species with a yellow-banded abdomen and antennae that are not swollen apically. Easily separated from the other (Tenthredo temula) by the larger size (body length to 14 mm) - in fact it is one of the largest British Tenthredo species. Females have tergites 4 and 5 entirely yellow; also the tibiae (except extreme tips), tarsi, cenchri, scutellum, tegulae, humeri and lower face. The slimmer males have tergites 3-6 and much of 2 yellow. The hind tibiae and tarsi are more extensively darkened than in the females.

Unless identified by a recognised expert, a photo is required. If the photo doesn't show the key ID features, then in the comments box describe the size and identifying characters you have observed.

Woodland and well wooded areas.

Adults fly from May to July and do not appear to be regular flower visitors.

The caterpillar-like larvae feed on larger grasses such as False-bromes and Cock's-foot.

Tenthredo maculata is widespread but localised in England and Wales but scarcer in Scotland.

Rare in Leicestershire and Rutland.  The Warren Hills record of 28 May 2023 is the first for VC55.
 

https://www.sawflies.org.uk/tenthredo-maculata/