A large black and green species similar to Tenthredo mesomela and mioceras. In obsoleta the mesopleura are black with a narrow subvertical green stripe whereas in the other two species the mesopleura are largely green with a wide black stripe. The stigma and costa of the fore wing and most of the upper surfaces are black.
A moorland species. Larvae feed on ribwort plantain.
Size: 9.5 - 12.5mm
Distribution: England, Scotland, Ireland
Flight period: June to July
Plant associations: Plantago lanceolata (ribwort plantain)
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
Fekete, K. (2018) Beginner’s guide to identifying British Tenthredo, Natural History Museum, London. http://www.nhm.ac.uk/content/dam/nhmwww/take-part/identification-trainers/sawflies-guide-id-trainees.pdf [Accessed 26Apr2019]