Urocerus flavicornis - Yellow-horned Horntail

Britain is not part of the natural range of this widespread Nearctic species. Stephens (1835) reported examples taken in and near London in August not mentioning which year. There have been no subsequent records at time of review. Some authors treat flavicornis as a subspecies of Urocerus gigas so the occasional introduction of flavicornis could be overlooked (Musgrove, 2022).

The eye spots on the head are widely separated as in gigas. The female abdomen is yellow to reddish brown on tergite 2, 7 and 8 (in the basal half) with the remainder black. The male abdomen is yellow with black basally and apically.

Urocerus flavicornis larvae feed in timber of coniferous trees and take 2 to 3 years to develop.

Jump to other Urocerus species

Size: 12 - 40mm

GB IUCN Status: Not Applicable
GB Rarity Status: Not Applicable

Distribution: England

Flight period: June to October

Plant associations: Pinaceae (coniferous trees)


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. 2022. A review of the status of sawflies of Great Britain - Phase 1: families other than Tenthredinidae. Natural England, unpublished

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.