Euura piliserra - piliserra group (formerly Phyllocolpa piliserra (Thomson, 1863))
See Liston et al (2017) for determination.
Euura piliserra larvae feed on common osier and Holme willow. Larvae in this group cause the outer leaf margins to curl down and in towards the mid vein creating two tubes with multiple larvae in each. They feed on the lower surface and then leave the tubes and eat the whole leaf-blade leaving the midrib intact.
Size: Female: 4.7 - 5.8mm, male: 4.9 - 5.6mm
Distribution: England, Scotland, Ireland
Flight period: Bivoltine, May to June, July to August
Plant associations: Salix viminalis and Salix dasyclados (common osier and Holme willow)
Benson, R.B., 1952. Handbooks for the Identification of British Insects. Hymenoptera, Symphyta, Vol 6, Section 2(a-c), Royal Entomological Society, London
Liston, A.D., Heibo, E., Prous, M., Vårdal, H., Nyman, T. and Vikberg, V., 2017. North European gall-inducing Euura sawflies (Hymenoptera, Tenthredinidae, Nematinae). Zootaxa, 4302(1), pp.1-115.
Liston A, Knight G, Sheppard D, Broad G, Livermore L (2014) Checklist of British and Irish Hymenoptera - Sawflies, ‘Symphyta’. Biodiversity Data Journal 2: e1168. https://doi.org/10.3897/BDJ.2.e1168