Ichneumon Wasp 'Heinrichiella obscura'

I photographed this wasp in a very large 'set-aside' field close to both my house and to my heart. That heart was broken in 2021 when I arrived one day in the first week of August to find the whole thing had been mechanically mown to the ground, right at the height of the summer season.

I spend the next few months lobbying via twitter for the field to be left untouched in 2022 until later in the season to allow many of the insects present to complete their lifecycle.

When this was finally agreed (to my obvious delight) I decided to document the wildlife still active in the field after the first week of August 2022, to demonstrate what had benefited from that decision.

Why am I detailing this?

Because one of the insects I documented (on 13th August and again on 10th September) was Heinrichiella obscura which, it transpired, was not only a new species to Britain, but also a new genus.

Not that I had any idea at the time, so this was nothing more than pure chance.

Until 2019 this wasp was one of two species in the genus 'Hellwigia'. However it turns out, not only were those two species highly divergent from all other Ichneumonidae, they were also divergent from each other, leading to a reclassification of this wasp as an Ophioninae, Heinrichiella obscura.

It appears H. obscura probably attacks final instar host larvae (in this case, of Geometridae) as appears to be typical for European Ophioninae and like many of its host species is therefore bivoltine.

I've spent several days attempting to obtain some live specimens for UK experts to study (as requested) but have thus far been unsuccessful.

Anyway, I cannot think of a greater justification for delaying the mowing of the field in question, than this discovery, unless of course, there was another...?

PS: No formal record has yet been filed in the UK because iRecord doesn't currently have the Heinrichiella genus on its database, but I've been assured it will be added in due course.

PPS: I somehow neglected to mention, Heinrichiella obscura is known to feed on 'Clematis vitalba', otherwise known in the UK as 'Traveller's Joy'. No surprise then, to tell you the field where I located the wasp is absolutely covered in Clematis vitalba.

Significantly, it flowers from mid summer to early autumn and would not have been alloowed to do so, except on the margins, had the field in question been mown in early August.