Euura respondens - Cryptic Willow Nematine

This member of the Euura bergmanni group was added to the British list by Ian Andrews in 2021. Females are difficult to separate from Euura oligospila in morphology but the male penis valve is reliable. Females also closely resemble Euura bergmanni and Euura sylvestris. Euura respondens has a more rounded head in dorsal view than does E. bergmanni. The saw lancet has the second to fourth sutures angled obliquely and straight to weakly curved, apically. In E. oligospila and E. sylvestris those sutures are weakly to distinctly curved apically.  

In life, the males have a yellow to brown ground colour with a varying extent of black. The stigma is fairly uniformly pale, and the pronotum is extensively pale. The females are often green in life but the ground colour may be yellow. 

Euura respondens larvae feed on crack willow. The larvae are much like those of Euura oligospila.

Jump to other Euura bergmanni group species

Size: Female: 6.0 - 9.0mm, male: 4.5 - 8.0mm.

Status: data deficient

Distribution: England

Flight period: Multivoltine, April to August

Plant associations: Salix fragilis and other Salix spp. Occasionally on Populus spp. (crack willow, other willows and occasionally on poplars)


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.

Muche, W.H., 1974. Die Nematinengattungen Pristiphora Latreille, Pachynematus Konow und Nematus Panzer (Hym., Temthredinidae). Deutsche Entomologische Zeitschrift, 21(1/3), pp.1-137.

Prous, M., Liston, A., Kramp, K., Savina, H., Vårdal, H. and Taeger, A., 2019. The West Palaearctic genera of Nematinae (Hymenoptera, Tenthredinidae). ZooKeys, 875, p.63-127

Prous, M., Liston, A., Mutanen, M. 2021. Revision of the West Palaearctic Euura bergmanni and oligospila groups (Hymenoptera, Tenthredinidae. Journal of Hymenoptera Research.