Males are rare. In the female the head is orange-red with the anterior of the postocellar area black, but the black colouring can be extensive across the entire head. In the male the head is almost always darkened so that only the labrum, clypeus, more or less the orbits are orange-red. The thorax is black with yellow-red on the posterior corners of the pronotum, the tegulae, sometimes the sides of the prescutum and rarely the mesopleura and metapleura. The abdomen is orange-red at least at the sides and below. If the abdomen is extensively darkened above, then at least the hind margin of the tergites is orange-red. The legs are yellow with black is on the bases of the coxae and the top of the tibiae and tarsi.
Euura nigricornis larvae feed on poplars and willows.
Size: Female: 6.0 - 8.0mm, male: 6.0 - 7.0mm.
Distribution: England, Scotland, Wales, Ireland
Flight period: May to June, July to August
Plant associations: Populus spp. and Salix spp. (poplars and willows).
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
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