Hunting wasps ? I.D. ?

[stevepl]

Hello all,

A while ago I photographed what I believe to be Hunting Wasps feeding from an umbellifer before the urge to go and hunt/egg lay.

I'm hoping someone can confirm that they are Hunting Wasps and if possible which one ?

There's a pic here :

Hunting Wasp ? - Wild About Britain Pics

Thanks for reading this :-)

Steve :-)

[oxycera]

Sawflies

[stevepl]

Thanks John.

[stevepl]

I'm reliably informed by a professional ecologist that they are male Ichneumon, (they have waists as per all wasp species), but they couldn't put a name to them.

If anyone would like to hazard a guess as to which genus it would be appreciated, thanks.

Steve :-)

[Jason Green]

Evening Steve,

I hope you've been keeping well since we last spoke.

Originally Posted by stevepl

A while ago I photographed what I believe to be Hunting Wasps feeding from an umbellifer before the urge to go and hunt/egg lay.

You had the urge to go and hunt/egg-lay? Oh, the... !!

As for the ID, I'm with John. The wing-venation looks incorrect for Ichneumonidea, and there is no petiolate link between the thorax and gaster. Any apparent constriction is I believe due to the yellow pigmentation on the insect merging-in with the pale shades of the Umbellifer. These individuals on look-value remind me of a few Sawflies I saw in a meadow regularly in June/July last year. I had them down as Cephidae.

Compare the wing-venation of your Sawflies to this Cephidae specimen: http://www.mnhn.lu/recherche/pics/symph/big/020.jpg, and then compare with Ichneumonidae: http://www.drawwing.org/files/imagec...nidae.svg_.png

...you'll notice the venation of the Sawfly is a lot 'busier' than the Ichneumon.

The surest way to tell the difference is in examining the 'waist'; Ichneumons have a petiolate section, whilst the gaster of Sawflies joins straight on (no waisted section). It's difficult to tell that from your photo though as they are sat at the wrong angle, but is more in evidence on the right-j=hand one taking off.

Take care,

Jason

[stevepl]

Thanks Jason, I'll do as you advise and have a look at the links you have offered, you could well be right

Steve :-)

[Jason Green]

I was mainly swayed by John's ID. On a second-glance the differences are more obvious.

These aren't, in my opinion, the most obviously sawfly-lookers. Not like the often thicker-set Tenthredinidae.

[oxycera]

As Jason says, they're cephid type sawflies. Does the 'ecologist' not want to share his views with us?

[stevepl]

Hi John, thanks for that.

I have suggested my friend join the site a few times, but as yet he hasn't !

Having looked through more pic's taken at the time they do have a pale green triangle on the upper side which does in some pic's give the appearance of a much more tapered waist than is the case, which is probably what mislead Bill.

I've just uploaded a few more pic's - for clarity and interest :-) They are here :
Sawfly ? - Wild About Britain Pics

Sawfly ? - Wild About Britain Pics

Sawfly ? - Wild About Britain Pics

Sawfly ? - Wild About Britain Pics

Sawfly ? - Wild About Britain Pics

Hunting Wasp ? - Wild About Britain Pics

Jason, I forgot to say before, I haven't been too bad, thanks for asking :-) Hope you have been well too ?

Thank you both again for your help with the identification and advice.

Steve :-)

[stevepl]

Thanks to John and Jason I went for a hunt around the net. I have found this web page and image from the Czech Republic :

BioLib - Calameuta filiformis - Image

Of the Reed Stem Sawfly, Calameuta filiformis it looks very similar and as the ones I photographed were near to the River Derwent on the outskirts of Derby it seems a likely candidate.

I've also been to the NBN Gateway site, there's one record for this species in Nottinghamshire but none for Derbyshire, it could of course just be a case of under recording !

Thanks again John and Jason.

Steve :-)