County ant recorder Phil Attewell was excited to photograph and video what he thought was a female Giant Woodwasp Urocerus gigas, in woodland near Radlett during August. But he was even more delighted when Sawfly UK group organiser Andrew Green responded to his posting on iRecord by identifying it as the much rarer Yellow-headed woodwasp Urocerus augur.
There have been fewer than a handful of British records for the species and none previously from Hertfordshire. Its distinguishing characters compared with Giant Woodwasp include a greater extent of yellow colouring on the head, and black markings on the legs. Previous records have been associated with imported timber, but the Radlett specimen was on mature Scots Pine in a woodland belt near arable fields. Even more interestingly, Phil's video shows it ovipositing on Scots pine, thought to provide the first national evidence of breeding.
Phil said: "The only other records shown on the NBN (National Biodiversity Network) Atlas are in east Norfolk and north Lincolnshire. It was a very impressive insect, but at the time I had no idea it was such a rarely recorded one. A pleasant surprise for what was a casual ramble in local countryside!"