Rarely encountered in Britain and Ireland. The female is black on the tergites above but reddish-brown laterally and beneath. The scutellum is densely clothed in pale hairs. The two apical tergites are densely clothed with silky, adpressed pubescence. Males abdomen is coloured as per the female and the scutellum is similarly clothed.
Trichiosoma vitellina larvae feed on willows.
Size: 13 - 24mm
Distribution: England, Scotland, Wales, Ireland
Flight period: May to June
Plant associations: Salix spp. (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
Viitasaari, M. 1989: Taxonomic notes on the genus Trichiosoma Leach (Hymenoptera, Cimbicidae) II. - Annales Entomologici Fennici, Helsinki 55 (3): 111-129