Three predominantly black and white Pachyprotasis species in Britain and Ireland can cause confusion; rapae, variegata and simulans.
Females of variegata are readily distinguished through having a red hind femora and tibia but both rapae and simulans have black and white legs in both sexes. Pachyprotasis simulans has tergites with white apical margins conspicuously thickened on the mid-dorsal line. In rapae the apical margins are either not white on the median line, or are narrow and not thickened on the median line. The frons in simulans is shining with only faint coriaceous sculpture, whereas in variegata this sculpture is more noticeable between dense, shallow punctures.Larvae feed on figworts, goldenrod and ragworts.
Size: 6.5 - 7.5mm
Status: Very rare
Distribution: England, Scotland, Wales
Flight period: May to June
Plant associations: Scrophularia spp., Solidago sp., and Senecio spp. (figworts, goldenrod and ragworts)
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