The antennae of Tremex species are short by comparison to other Sirid wood wasps. There is some variation in colour within this species. Females are varying degrees of brown on the abdomen with yellow across the bases of the tergites giving a striped appearance. The tibia and tarsae are yellowish with darker femora. Males are more uniformly brown to orange-brown with hind legs that are dark but ringed with yellow on the tibia and femora.
Larvae feed inside timber of dead and dying deciduous hardwoods. Larval development lasts 2 or 3 years and may pass through 11 instars.
Size: 20 - 30mm
Status: Introduced, not established.
Distribution: England, Scotland
Flight period: June to October
Plant associations: Fagus spp., Ulmus spp., Acer spp., Quercus spp., etc. (beech, elms, maples, oaks, etc.)
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
Schiff, N.M., Goulet, H., Smith, D.R., Boudreault, C., Wilson, A.D. and Scheffler, B.E., 2012. Siricidae (Hymenoptera: Symphyta: Siricoidea) of the western hemisphere. Canadian Journal of Arthropod Identification 21: 1-305, 21, pp.1-305.