Length 5.5 to 8 mm. This is an all-black sawfly with orange legs.

Larvae are a pale grey with pink and green tones. They lack the black spot on the top of the anal segment that is found on larvae of Ametastegia equiseti.

Found around hedgerows and flower meadows.

April to September.

It is associated with a wide range of herbaceous plants, including Fat-hen, Redshank, Docks, Plantains, Purple loosestrife and Willow.

Widespread in Britain.

Infrequent or under recorded in Leicestershire and Rutland.

https://www.sawflies.org.uk/ametastegia-glabrata/