Benson (1952) knew of only two records, but this species seems to be on the increase and has been found much more widely in recent years, occurring locally north to Glasgow (Musgrove, 2023).
A small black bodies insect with infuscated wings having noticeable subhyaline apices. The tegulae are black and the tibiae and basal tarsal segments are brownish-white. The apical tergites are smooth. Males are unknown.
Profenusa thomsoni larvae mine in the leaves of birch.
Size: 3 - 4mm
GB IUCN Status: Least Concern
GB Rarity Status: None
Distribution: England, Scotland, Wales
Flight period: May to July
Plant associations: Betula spp. (birches)
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
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 Natural England, unpublished