Males are unknown. Abdomen brown above and the legs almost entirely white. Adults are elusive.
Metallus lanceolatus larvae mine the leaves of wild and cultivated avens creating blotch mines.
Size: 3.5 - 4.5mm
Distribution: England, Scotland, Wales
Flight period: Bivoltine, May to June, July to August
Plant associations: Geum spp. (wild and cultivated avens)
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