Usually a black, or reddish-brown bodied insect, though very rarely yellow forms occur. Males may have a red banded abdomen. The wings in both sexes have a clearly defined fuscous apical band. The pale cream membrane in the centre of the first tergite contrasts strikingly with the dark sclerotised portion. The yellow forms can be confused with Cimbex luteus and Cimbex connatus but only femoratus has clearly defined, dark, apical bands on the fore wings.
Larvae feed on birches.
Size: 20 - 28mm
Distribution: England, Scotland, Wales, Ireland
Flight period: May to August
Plant associations: Betula spp. (birches)
The National Biodiversity Network records are shown on the map below. (See terms and conditions)
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