Group viminalis

Description follows Liston et al, 2017. This group form bladder or pear-shaped galls on willow leaf blades on the mid-vein. Galls formed on lateral veins do not reach maturity. In Britain, the hostplants are, for the most-part, upland species. Only pedunculi, vesicator and viminalis utilise more widespread hostplants. Species in this group are univoltine, except for vesicator and viminalis which are bivoltine. The characteristics of the group are as follows. The mandibles are symmetric with each tapering gradually from the base to the apex. The cross vein 2r-m is usually present on the forewing submarginal cells. The supraclypeal region is densely setose. The antennae vary by species from short to long long.  The cerci are moderate being about 3.5 to 6 times as long as their maximum width and reaching at least half way along the sawsheath. The penis valve of the males has small spines ventrally. 

Group viminalis

Subgroup aquilonis

Euura aquilonis (Benson, 1941) = Pontania aquilonis Benson, 1941

Subgroup aquilonis

Euura arbusculae (Benson, 1941) = Pontania arbusculae Benson, 1941

Euura crassipes (Thomson, 1871) = Pontania crassipes (Thomson, 1871)

Euura herbaceae (Cameron, 1876) = Pontania herbaceae (Cameron, 1876)

Subgroup viminalis

Euura arcticornis (Konow, 1904) = Pontania arcticornis Konow, 1904

Euura collactanea (Förster, 1854) = Pontania collactanea (Förster, 1854)

Euura myrsiniticola (Kopelke, 1991) = Pontania myrsiniticola Kopelke, 1991

Euura pedunculi (Hartig, 1837) = Pontania pedunculi (Hartig, 1837)

Euura saliciscinereae (Retzius, 1783) = Pontania saliciscinereae (Retzius, 1783)

Euura samolad (Malaise, 1921) = Pontania samolad Malaise, 1920

Euura viminalis (Linnaeus, 1758 = Pontania viminalis (Linnaeus, 1758)

Subgroup vesicator

Euura pustulator (Forsius, 1923) = Pontania pustulator Forsius, 1923

Euura vesicator (Bremi-Wolf, 1849) = Pontania vesicator (Bremi-Wolf, 1849)

References:

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, 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

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.