Group bergmanni

Description follows Prous et al, 2021. This group of green nematine sawflies are morphologically similar to the Euura oligospila 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 bergmanni group, the valviceps (comprised of the paravalva and pseudoceps) is usually broader apically and without a 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. The key to the bergmanni and oligospila groups is in Prous et al (2021). The viridis subgroup (brevivalvis, dispar, viridis, glutinosae) sits within the bergmanni group. Viridis subgroup females can be recognised by saws and the tendency to have a relatively long malar space compared to most other species in the bergmanni and oligospila groups.

Most species within the group are multivoltine. They all feed on Salix spp. (willows), Alnus spp. (Alders) or Betula spp. (birches). The larvae are green, solitary feeders and later instars feed from the edge of the leaf. 


Species list: 

Euura bergmanni (Dahlbom, 1835) = Nematus (Pteronidea) bergmanni Dahlbom, 1835

Euura brevivalvis (Thomson, 1871) = Nematus (Pteronidea) brevivalvis Thomson, 1871

Euura dispar (Zaddach, 1876) = Nematus (Pteronidea) pseudodispar (Lindqvist, 1969)

Euura glutinosae (Möller, 1882) = Nematus (Pteronidea) viridissimus Möller, 1882

Euura respondens (Förster, 1854) = Nematus (Pteronidea) respondens Förster, 1854

Euura sylvestris (Cameron, 1884) = Nematus (Pteronidea) sylvestris Cameron, 1884

Euura viridis (Stephens, 1835) = Nematus (Pteronidea) viridis Stephens, 1835

 

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