Female: 8 to10 mm, male: 6.5 to10 mm.  In the female the head and mesonotum are mainly black and the abdomen is orange-yellow with some infuscation basally. The scutellum is mostly black but may be narrowly margined with yellow. In the male the mesopleura, the lower part of the face and the underside of the antennae are yellow and the abdomen is yellow with at most the basal two tergites marked with black. The stigma is black.

Adult  Larva

Adult: Unless identified by a recognised expert, a photo is required and the specimen should be examined with a microscope. In the comments box, state the key or ID method used and describe the size and identifying characters.

Likely to be found where the larval food plants, White Willow and Crack-willow occur.

Flight period: May to June, July to September.

Euura salicis larvae feed on White Willow and Crack-willow.

Local in Britain, but may be fairly frequent in suitable locations.

Rare in Leicestershire and Rutland.

https://www.sawflies.org.uk/euura-salicis/