Euura weiffenbachiella is a species of sawfly belonging to the family Tenthredinidae (common sawflies). The larvae forms galls on creeping willows (Salix repens). E. weiffenbachiella is one of a number of closely related species which is known as the Euura atra subgroup.
The shape of the gall is variable, probably depending on where the egg is laid;
Found on creeping willow (S. repens) and S. rosmarinifolia.
Other similar looking species in the Euura atra subgroup are,
Liston et al. records the sawfly from central and northern Europe, and east to Yakutia. Redfern et al. records the gall from Great Britain (Scotland) and Ireland.