Group oligospila

Description follows Prous et al, 2021. This group of green nematine sawflies are morphologically similar to the Euura bergmanni group and other green nematines including Euura poecilonota and hypoxantha.  Males of the species in the group, and similar nematines, are easier to distinguish from each other than the females using the attributes of the penis valves. In the oligospila group, the valviceps (comprised of the paravalva and pseudoceps) is usually about as broad  apically as it is basally and there is a weak to pronounced constriction in the middle. Euura bergmanni group penis valves usually also have a distinctly deeper invagination between the valvispina and paravalva than in the oligospila group where it is indistinct. The key to the bergmanni and oligospila groups is in Prous et al (2021). 

Most species within the group are multivoltine. The two European species of the group both feed on Salix spp. (willows). The larvae are green, solitary feeders and later instars feed from the edge of the leaf. 


Species list: 

Euura frenalis (Thomson, 1888) = Nematus (Pteronidea) frenalis Thomson, 1888

Euura oligospila (Förster, 1854) = Nematus (Pteronidea) oligospilus Förster, 1854

 

References:

Benson, R.B., 1958. Handbooks for the Identification of British Insects. Hymenoptera, Symphyta, Vol 6, Section 2(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

Prous, M., Liston, A., Mutanen, M. 2021. Revision of the West Palaearctic Euura bergmanni and oligospila groups (Hymenoptera, Tenthredinidae. Journal of Hymenoptera Research. http://zoobank.org/1459B177-AF2B-4D39-9483-E8BA21E70E67