Flies? from Milton Keynes

[turntostone]

Anyone able to id either of these flies? photographed on the last of the Ivy flowers in my Garden in Milton Keynes. Photo taken October 30.

I know its a bit blurred but even Generic ID would be of use.

Thanks
Gordon

[Jason Green]

Evening Gordon,

The first fly (top-left) is most likely a Braconid wasp (impossible from photos, nearly as tough with specimens!). No strong feeling about the second - try Scathophagidae.

Take care,

Jason

[oxycera]

I agree with Jason with dung-fly, no doubt a common one.

[turntostone]

Thanks guys

I guess I need to get better photos.

Gordon

[Jason Green]

John is better-placed to comment on the Scathophagid, but the Braconid would need a specimen - even with 'perfect' photographs. The parts you need to see are too subtle for photo-based IDs to species-level unfortunately, and a lack of literature and UK experts in this family make it pretty difficult even then.

[JRsbugs]

The flies are a mating pair of most likely Scathophaga stercoraria, they have black antennae and are pretty common. I keep seeing mating pairs on my Ivy.

Unfortunately not all wasps are either Braconids or Ichneumons, there is an amazing number of families and without seeing wing venation and having more indepth knowledge on the subject the less said the better!

Spider-hunting wasps in the family Pompilidae are as good a bet as any! There's a lot of look-alikes amongst those too.

Janet

[Jason Green]

Pompilidae? I doubt it. An interesting suggestion, though the strength to the curve of the central/last few flagella suggest a greater number of segments than they have - typically 10 to 12. Braconids have a minimum of 16 and usually many more, which I think can be deduced here.

Hind legs - the length of the hind femur and tibia together often reaches to the tip of the abdomen in Pompilids, whereas you can see here, that part is much shorter.

Wing venation - Braconids don't tend to have too much at the top-end, whereas with Pompilidae it is more like a lot of other big Aculeates - you'd see the marginal/sub-marginal cells which isn't apparent here.

So, I still believe it's Braconidae

[JRsbugs]

Originally Posted by Jason Green

Pompilidae? I doubt it. An interesting suggestion, though the strength to the curve of the central/last few flagella suggest a greater number of segments than they have - typically 10 to 12. Braconids have a minimum of 16 and usually many more, which I think can be deduced here.

Hind legs - the length of the hind femur and tibia together often reaches to the tip of the abdomen in Pompilids, whereas you can see here, that part is much shorter.

Wing venation - Braconids don't tend to have too much at the top-end, whereas with Pompilidae it is more like a lot of other big Aculeates - you'd see the marginal/sub-marginal cells which isn't apparent here.

So, I still believe it's Braconidae

So now you have microscopic vision as well as swallowing the dictionary of entomology?

I threw Pompilidae into the pot, as I said it's as good a guess as any! Emphasis on the word guess.

However, it would be interesting to know what someone with a degree of experience with wasps could say from the distant photo which really gives little or no clue as to the number of antennal segments, wing venation etc.

As a matter of interest, here's some pics of Pompilidae to compare.. but I would not like to even suggest a family based on the photo given! For one I do not have the experience, neither do you Jason!

Category:Pompilidae - Wikimedia Commons

Oh you know I really do have better things to do with my time, but it is maybe educational in a sense. Once again I don't think people should be so misled by someone who does not know!

[Jason Green]

Janet, I only said Likely in the first place! I do stand by that though. With the keys I'm using at the moment you have to use these words - it'd be pretty confusing otherwise. Swallow a dictionary? I don't think my teeth would be sharp enough. I am hungry, though!

Anyway, look through those Pomps you've posted and compare again. Take this one for example:

File:Auplopus carbonarius fg01 20060623 Nied Garten.jpg - Wikimedia Commons

All black, with shaded wings. Similar then to the wasp put up by TTS. Now, as I see it when comparing this to the wasp in question:

• The length of the hind femur and tibia
  Imagine stretching the rear legs backwards - you can clearly see the tip of the Pompilid's hind tibia would extend beyond the abdominal tip (not including any ovipositor). I doubt the wasp's final tarsi in the first post would even touch the tip!
• The 'waist' section
  I don't know of any Pompilid with a constricted first tergite forming a petiole, yet it's an obvious feature in the OP's picture
• The gist from the head and eye location
  Pompilids rare, if ever, have this cylindrical head-shape. It is, however, the same sort of shape you'd find on a lot of proven Braconids.

I have three Pompilidae myself, and am working hard to get the key to these - it's out of print. I also have a Braconid wasp, and the differences are obvious comparatively. It gives you a great point of comparison, and from this you build a good visual interpretation of these, and for me I can tell the differences based on this image. Lastly, it's been two months since I saw my last Pompilid - they prefer hot weather, I never saw any unless it was 18' or over.

I wonder if TTS knew one image could conjure such discussion!

[JRsbugs]

Originally Posted by Jason Green

• The length of the hind femur and tibia
  Imagine stretching the rear legs backwards - you can clearly see the tip of the Pompilid's hind tibia would extend beyond the abdominal tip (not including any ovipositor). I doubt the wasp's final tarsi in the first post would even touch the tip!

• I say Jason, what big eyes you have to be able to see that!
  
  

  The 'waist' section
  I don't know of any Pompilid with a constricted first tergite forming a petiole, yet it's an obvious feature in the OP's picture

  The gist from the head and eye location
  Pompilids rare, if ever, have this cylindrical head-shape. It is, however, the same sort of shape you'd find on a lot of proven Braconids.

Head shape, look at this one..

http://www.natureconservationimaging...gerrimus-1.jpg

No petiole? Look here..

Spider wasp - Wikipedia, the free encyclopedia

I wonder if TTS knew one image could conjure such discussion!

Discussion is always healthy as long as one is not blinded by what one thinks one knows. As I have said before, assumption is the mother of all..

Lastly, I think it would be a good exercise in recognition to look at the very good artist plates showing several Braconid wasps..

Horace Knight Insect Prints for Sale

Another lastly, look at all of the superfamilies on HYMIS, that will give anyone a good idea of the variablity of wasps, and should make one realise that having half a dozen or so specimens will not make anyone an expert.

Fotogalerie - Hymenoptera Information System (HymIS)