Recorded widely in southernmost England and Wales, south from Pembrokeshire and the Chilterns, as well as more isolated records in East Anglia (Musgrove, 2023).
A smaller yellow and black species. The antennal flagellae are entirely black but with yellow scapes. The underside of the abdomen is mostly black. The yellow bands on the tergites do not broaden at the sides. The tegulae are entirely black. The apex of the hind tibia is black in the male and reddish in the female. Associated with marsh edges and chalk downs.
Tenthredo thompsoni larvae feed on marjoram, mints, plantains and gypsywort. Larvae are similar to Tenthredo mandibularis but lack the white warts that are present in the yellow spots in mandibularis.
Size: 9 - 11mm
GB IUCN Status: Least Concern
GB Rarity Status: None
Distribution: England, Wales
Flight period: July to September
Plant associations: Origanum vulgare (Marjoram), Mentha aquatica (Water Mint), Plantago (Plantains) and Lycopus (Gypsyworts)
Benson, R.B., 1952. Handbooks for the Identification of British Insects. Hymenoptera, Symphyta, Vol 6, Section 2(a-c), Royal Entomological Society, London
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]
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
Musgrove, A.J. 2023. A review of the status of sawflies of Great Britain - Phase 2: The Athaliidae and the Tenthredinidae (excluding Nematinae). Natural England, unpublished