Is this a sawfly?

Sinaves · #1 (**permalink**) 03-09-2009, 07:47 PM

Hi,

I took this photo in June in S. Yorks:

It looks very similar to a sawfly that I saw this August that someone 'id'ed for me:

Unidentified hymenoptera

but it also looks like some parasitic wasps in my basic insect id book. My book says that the way to recognise a sawfly is that it doesn't have an obvious waist between the thorax and abdomen though this diagnostic feature is not visible in this picture.

All in all I would say that it looks more like a sawfly, but I am hoping someone can let me know whether or not this is the case, how they know, and also if possible, what species/genus/family of Hymenoptera it is.

Thanks very much

Ed

Jason Green · #2 (**permalink**) 03-09-2009, 08:17 PM

Evening Ed,

Looking at the head, the large eyes give it a deep and chunky appearance, and is quite robust-looking generally. It says to me it's a Spider-hunting Wasp, family Pimpilidae. You see the hooks on the back legs? I believe it uses these to hook the spider to as it flies/walks.

Sorry, no idea of species - though the white antennal segments look distinctive.

Take care,

Jason

JRsbugs · #3 (**permalink**) 03-09-2009, 08:17 PM

Looks like a sawfly, the white area on the face is typical as is the white on the antennae.

Janet

JRsbugs · #4 (**permalink**) 03-09-2009, 08:23 PM

It looks a lot like Tenthredo livida but I'm not sure about the leg colour.

Sinaves · #5 (**permalink**) 04-09-2009, 09:59 PM

Hi Jason, Janet,

I had a look online at photos and it is very similar to T. livida which I'm taking it to be (unless there are any similar sp). e.g. see Symphyta

However I have to say the differences with the the spider-hunting wasps are not clear to me. I suppose the ability to differentiate comes with experience.

Thanks for both your replies.

Ed