This species overwinters as an egg and subsequently adults emerge late in the year. The female is mainly reddish-brown excluding parts of the mesonotum and basal tergites. The male is black except for the underside of the abdomen.
Neodiprion sertifer larvae feed gregariously on old needles on pines, especially Scots pine. They can be prolific and cause damage to young trees. The larvae usually cocoon amongst the pine needles in the tree.
Size: 7 - 9mm
Distribution: England, Scotland, Wales, Ireland
Flight period: July to October
Plant associations: Pinus spp. especially silvestris (pines especially Scots pine)
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