 Tachinidae: Dexiinae
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| Susan R Walter |
Posted on 03-03-2007 13:46
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 Member Location: Posts: 1794 Joined: 14.01.06 |
I think this is sf Dexiinae, but can't get any further. 3 post sutural ia, very short hairs on arista, bristlets on R4+5 to about 3/4 of the way to the cross vein, R5 narrowly open. The body is quite shiny black, but fairly substantially dusted. 6mm. From 20 May 2006, east London cemetery park. Susan |
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| Susan R Walter |
Posted on 03-03-2007 13:47
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Member Location: Posts: 1794 Joined: 14.01.06 |
Another view.
Susan |
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| Zeegers |
Posted on 03-03-2007 13:56
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Member Location: Posts: 18446 Joined: 21.07.04 |
Hi Susan If it is, indeed, a Tachinid, this should probably be Phorocera. However, it might be a Sarcophagidae / Rhinophoridae ? Difficult to tell from these pictures Theo |
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| Susan R Walter |
Posted on 03-03-2007 14:06
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Member Location: Posts: 1794 Joined: 14.01.06 |
Theo Blimey - that was quick! What do we need to know to tell the difference? I can look, and try to take some better photos. These small dark flies are always difficult with the equipment I have though. Chris has offered to ID if I post the specimen to him, but it is always better if I can do it myself with a little help. Susan |
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| Zeegers |
Posted on 03-03-2007 14:41
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Member Location: Posts: 18446 Joined: 21.07.04 |
The quickness was sheer accidental, or luck. So, let's start with the eyes: if these are clearly hairy, it must be Tachinidae. Let's see how quick you are Theo |
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| Susan R Walter |
Posted on 03-03-2007 14:56
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Member Location: Posts: 1794 Joined: 14.01.06 |
The eyes are not what I would call *clearly* hairy. They are fairly sparsely covered in very short hairs. I have checked Chris's website and Phococera don't seem to have M petiolate and this specimen does. I am now seriously wondering about Sarcophagidae, but need to do a bit more looking. Not Rhinophoridae because presumably the bend in the vein is too sharp? Susan |
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| Susan R Walter |
Posted on 03-03-2007 15:21
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Member Location: Posts: 1794 Joined: 14.01.06 |
I've had a look in the gallery and Nyctia sp (Sarcophagidae) seemed like an option, but Thomas Pape's website says Nyctia has very little microtomentum, so I assume my specimen is too heavily dusted. I had dismissed Rhinophoridae because Unwin's Key to the families of British Diptera says 'bend of vein 4 never sharp', but having looked at the gallery, the bend seems to be fairly sharp to me although perhaps not as sharp as my specimen. None of the ones in the gallery have petiolate M veins either. From a rather jizzy point of view, Phyto sp seems rather like my specimen - that rather long legged rather elegant look. Still stuck I'm afraid, but still looking. Susan |
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| Zeegers |
Posted on 03-03-2007 16:04
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Member Location: Posts: 18446 Joined: 21.07.04 |
Hi Susan You're right about Rhinophoridae, they never have a long appendix to the bend of vein M. To me, this is just a small species of Sarcophagidae / Sarcophagini, something like Helicophagella maybe. For this, the arista should be clearly plumose. Otherwise, I'm starting to get lost Theo |
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| Susan R Walter |
Posted on 03-03-2007 17:30
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Member Location: Posts: 1794 Joined: 14.01.06 |
I am now reasonably sure that this is Sarcophagidae, and I suspect that the long costal spine should tell us something, but I can't find enough descriptions of the possible UK genera to get any further. The arista is clearly plumose, but by no means 'bouffant'. The length of the hairs is about 2.5 times the width of the thickest part of the arista I would guess, and the hairs themselves are not particularly fine which adds to the impression that they are rather short (very short is an exaggeration, and having looked at them now under better light and magnification, I realise they are longer than I first thought. I had originally noted them as only about as long as the width of the arista). I'm giving up and going away now - to return shortly with an Anthomyid 
Susan |
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| Zeegers |
Posted on 03-03-2007 17:34
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Member Location: Posts: 18446 Joined: 21.07.04 |
Oke, let's try the 'official' feature for Sarcophagini: The hind coxa should bear some setulae (small bristles) on their backside. Be sure to first study this on a Sarcophaga carnaria, so that you get the drift. Then try it on this one. I suspect you will find similar setulae, confirming my suggestion. Theo |
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| Susan R Walter |
Posted on 03-03-2007 19:17
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Member Location: Posts: 1794 Joined: 14.01.06 |
Yep - clearly visible and similar to S carnaria. Many thanks for your help and patience with this one. Are we going to get any further with this one or should I drop it now with a sigh of relief? How many genera and subgenera in Sarcophagini, even in the UK? About a zillion, I think 
Edited by Susan R Walter on 03-03-2007 19:18 Susan |
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| Zeegers |
Posted on 03-03-2007 21:11
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Member Location: Posts: 18446 Joined: 21.07.04 |
Good news: not too many genera Bad news: mainly male genitalia features. For pro's Theo |
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| Susan R Walter |
Posted on 04-03-2007 14:57
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Member Location: Posts: 1794 Joined: 14.01.06 |
OK, so this one goes down as Sarcophagidae sub family Sarcophagiinae possibly Sarcophaga sub genus Helicophagella - there are 5 species of this sub genus in the UK.
Susan |
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| Zeegers |
Posted on 04-03-2007 19:26
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Member Location: Posts: 18446 Joined: 21.07.04 |
Hi Susan, that's great ! We are a lovely team, aren't we ? Theo |
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| Susan R Walter |
Posted on 05-03-2007 13:27
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Member Location: Posts: 1794 Joined: 14.01.06 |
Theo You are a very nice kind man and I certainly know more about Sarcophagidae than I did two days ago, because you were willing to help. Susan |
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| jorgemotalmeida |
Posted on 05-03-2007 13:30
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 Member Location: Posts: 9295 Joined: 05.06.06 |
wowo! Great thread and a lesson for HUMAN cooperation.  |
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| Susan R Walter |
Posted on 29-04-2007 13:08
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Member Location: Posts: 1794 Joined: 14.01.06 |
I sent this specimen to Del Smith, my county diptera recorder, and he has identified it as Sarcophaga (Heteronychia) dissimilis. He says 'They are not uncommon, very much under recorded.'
Susan |
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but don't see the image in the post.