This insect obligingly flew into my net.
No interactions present.
Thanks for ruling out Ichneumoninae. Is there a readily accessible source of information on these insects?
This site might be a good place to start with general keys and espcially on ichs likely to be found in light traps such as you ophionine. http://www.record-lrc.co.uk/forum/viewtopic.php?f=28&t=424.
Thank you for the link and its link to other useful resources.
PS. Note that the link to the checklist of Sawfly is incorrectly hyperlinked - the link is missing the "h" of "http:"
Thank you for your suggestion.
Lat/Lng: 52.669824480518, -2.5500297546387
OS grid ref: SJ629081