pun_logo

The Society for the study of flies (Diptera)

Affiliated to the British Entomological and Natural History Society (BENHS)

You are not logged in.

#1 2009-02-25 16:40:03

PeterB
DF Members
Name: Peter Bolson
From: North Cumbria
Registered: 2008-08-22
Posts: 90

Which muscid ?

I'd be very grateful for another ID. I don't as yet have access to a key for this family. I've still got the specimen if any more information is required.
Thanks
Peter


Uploaded Images

Offline

 

#2 2009-02-25 21:08:40

brianh
DF Members
Name: Brian Harding
From: Kidlington, Oxfordshire
Registered: 2008-10-27
Posts: 327

Re: Which muscid ?

I would look at the characters for Dasyphora cyanella which resembles Lucillia (Greenbottle/Blowfly), but 4th long vein bends gently forward (as in your picture) rather than sharply. Several related species. Becomes coppery with age.

Offline

 

#3 2009-02-26 12:15:28

PeterB
DF Members
Name: Peter Bolson
From: North Cumbria
Registered: 2008-08-22
Posts: 90

Re: Which muscid ?

Many thanks Brian.

Offline

 

#4 2009-02-26 14:03:23

Howard Bentley
Committee
Name: Howard Bentley
Registered: 2008-07-07
Posts: 795

Re: Which muscid ?

I go along with Eudasyphora cyanella (the newer name for the same fly - Muscids seem to change names more often than most). You don't say when the fly was taken, but it commonly appears very early in the year. There is another Eudasyphora - cyanicolor - which is less common. Cyanella has densely hairy eyes; in cyanicolor they are almost bare. I can't see eye hairs on your pictures, but check under the microscope.

Offline

 

#5 2009-02-26 16:23:42

PeterB
DF Members
Name: Peter Bolson
From: North Cumbria
Registered: 2008-08-22
Posts: 90

Re: Which muscid ?

Thanks Howard
I caught it this week & I can't see any hairs on the eyes. And just as I learn one name I have to forget it and learn another !
Peter

Offline

 

#6 2009-02-26 17:16:35

brianh
DF Members
Name: Brian Harding
From: Kidlington, Oxfordshire
Registered: 2008-10-27
Posts: 327

Re: Which muscid ?

Without wishing to cause too much confusion there is another candidate to eliminate - Neomyia species - which are also greenbottle lookalikes with wings similar to yours and bare eyes.
I looked at the pictures of Eudasyphora cyanicolor - eyes not hairy and the wing venation is right but it is shown as a blue fly.
Perhaps look carefully at the bristle patterns of candidates to see if that is informative.
As always you have the fly to examine in greater detail than can be seen in a picture, but without full descriptions of each candidate to be found in keys it may be difficult to be certain of identity.
What I have said is not to say that E. cyaniclor is wrong, only that it is better to be uncertain than to guess the wrong attribution.

Offline

 

#7 2009-02-26 17:45:09

PeterB
DF Members
Name: Peter Bolson
From: North Cumbria
Registered: 2008-08-22
Posts: 90

Re: Which muscid ?

Brian
What bristle features would tell me whether it was a Neomyia species or E.cyanicolor ? As I mentioned before I'm afraid I don't have a key to the muscids. Thanks
Peter

Offline

 

#8 2009-02-26 18:50:24

Andy chick
DF Members
Name: Andy Chick
From: Nottingham
Registered: 2008-02-26
Posts: 99
Website

Re: Which muscid ?

This is a copy of part of the rough and ready Green bottle key from Colyer and Hammond  with updated names

1 frons and Jowls Mettalic Green..........Neomyia (Muscidae)

   frons and jowls Not metallic Green........2

2 Vein 4 bowed or curved towards vein 3 not sharply bent ....3

  Vein 4 sharply bent towards vein 3 .....4

3 vein 1 hairy at base eyes hairy...........Eudasyphora (Muscidae)

  Vein 1 bare; eyes bare.......Pyrellia (muscidae)

Offline

 

#9 2009-02-27 11:51:01

Howard Bentley
Committee
Name: Howard Bentley
Registered: 2008-07-07
Posts: 795

Re: Which muscid ?

Brian suggests says that the wings of Neomyia species are similar to those of Eudasyphora, but the bend of vein 4 is angled - much sharper than is shown in Peter's photos. Figure 6 of Fonseca's key shows the two wings. In my experience these illustrations are accurate. Also, although it is true that colours may fade on older flies, I have never seen a Neomyia as dull as Peter's fly. E. cyanicolor is brighter and bluer, and perhaps I introduced a red herring there. The fly is a female, and eye hairs are less dense than in the males, but should still be obvious - may I suggest you try viewing against a black background? Some more features of E. cyanella from Gregor et al.: 2 pairs of blackish pre-sutural stripes (I think I can see these on the first picture); anterior spiracle pale yellowish; meron with several hairs under posterior spiracle.

Offline

 

#10 2009-02-27 13:44:01

PeterB
DF Members
Name: Peter Bolson
From: North Cumbria
Registered: 2008-08-22
Posts: 90

Re: Which muscid ?

The frons is a sort of dull grey-green colour.
The eyes are definately bare.
The anterior spiracle is pale yellowish.
I can't see any hairs on the meron below the posterior spiracle.
Not sure what you mean by pre-sutural stripes.
Still not sure how the vein numbers correspond to the old Comstock Needham nomenclture.

So which is it ?
Thanks
Peter

Offline

 

#11 2009-02-27 15:44:12

brianh
DF Members
Name: Brian Harding
From: Kidlington, Oxfordshire
Registered: 2008-10-27
Posts: 327

Re: Which muscid ?

With apologies if I have got it wrong but I have labelled your first picture with vein4 and pre-sutural stripes.


Uploaded Images

Offline

 

#12 2009-02-27 16:17:47

PeterB
DF Members
Name: Peter Bolson
From: North Cumbria
Registered: 2008-08-22
Posts: 90

Re: Which muscid ?

Thanks again Brian. That's very neat labelling - how did you do it ?

I've been a member of all sorts of different forums but I must say that this is the most helpful one I've come across smile

Offline

 

#13 2009-02-27 19:10:22

Howard Bentley
Committee
Name: Howard Bentley
Registered: 2008-07-07
Posts: 795

Re: Which muscid ?

I'd love to see this fly! How frustrating photographs can be! It looks to me as if Brian has labelled post-sutural stripes; the suture is the transverse crease across the thorax just in front of Brian's label. In front of this are the pre-sutural stripes. I think (though I can't be sure) that I can see 4, the outer 2 disappearing at the suture. However, all this is academic because the bare eyes make E. cyanella definitely wrong.

Offline

 

#14 2009-02-27 21:49:05

brianh
DF Members
Name: Brian Harding
From: Kidlington, Oxfordshire
Registered: 2008-10-27
Posts: 327

Re: Which muscid ?

Apologies Howard  for my ignorance, but at least I think that we now know which stripes are being referred to. As you say there appear to be two pairs of stripes, one pair fading before the suture, and the other continuing across the suture before fading (which I labelled).
As mentioned above the bend of long vein 4 in Neomyia is sharper than in these pictures so can be eliminated.
Concerning the eyes which appear to be bare - I have found in another context (on small Heteroptera at x80)  that if the hairs are fine I have to use very directional oblique lighting rather than my ringlight. However we have to accept that the eyes may be bare.

Offline

 

#15 2009-02-27 23:53:55

PeterB
DF Members
Name: Peter Bolson
From: North Cumbria
Registered: 2008-08-22
Posts: 90

Re: Which muscid ?

Howard - I can confirm that you are exactly right about the 4 stripes. I still can't see any hairs on the eyes. Maybe as Brian says they are very short. I have tried to get some closer photos to see what you think but they may not be any use.


Uploaded Images

Offline

 

#16 2009-02-28 14:05:07

Howard Bentley
Committee
Name: Howard Bentley
Registered: 2008-07-07
Posts: 795

Re: Which muscid ?

Many thanks Peter. This may turn out to be a prolonged correspondence about a very common fly, but perhaps we're all learning something along the way. You usually cannot see eye hairs by looking directly at the eye - you have to focus on the edge of the eye against a well-lit background. Sometimes a white background is best, and sometimes a dark one, depending on the colour of the hairs. Looking at your second picture, the facets of the eye on our left which are in focus are those which look straight at us; these are not the ones we need. Focus on the left-hand edge (as we look at the picture) where the edge of the eye is against the white background, and if there are any eye hairs they should be visible.

Offline

 

#17 2009-02-28 17:11:49

PeterB
DF Members
Name: Peter Bolson
From: North Cumbria
Registered: 2008-08-22
Posts: 90

Re: Which muscid ?

Hello Howard
This is the best I can do with my equipment. Perhaps I should invest in some extension tubes.
But having said that I still cannot see any hairs with the microscope using the techniques you describe.
Many thanks for your interest & patience.


Uploaded Images

Last edited by PeterB (2009-02-28 17:12:39)

Offline

 

#18 2009-02-28 18:08:44

Howard Bentley
Committee
Name: Howard Bentley
Registered: 2008-07-07
Posts: 795

Re: Which muscid ?

Thanks for the new picture, Peter. I think I can see short dark hairs at around the 8 o'clock position, but its very doubtful. If I'm wrong then I'm completely flummoxed as to this fly's identity! It's good to see someone taking an interest in the Muscidae - I think it's a fascinating family with lots of variety and good keys available. For some reason the Muscids seem rather neglected, so many thanks for this interesting thread.

Offline

 

#19 2009-02-28 23:25:45

PeterB
DF Members
Name: Peter Bolson
From: North Cumbria
Registered: 2008-08-22
Posts: 90

Re: Which muscid ?

Howard - I hope this will be my final posting on this subject, which certainly for me has been very instructive.
I have spent ages looking at these eyes with the microscope using different sorts of lighting & backgrounds and you'll be pleased & relieved  to hear that I am now finally convinced that there definately are very short hairs !
Does that mean that it is definately E.cyanella ?
The next one should be easy smile
Peter

Last edited by PeterB (2009-02-28 23:26:40)

Offline

 

#20 2009-03-01 17:46:07

Howard Bentley
Committee
Name: Howard Bentley
Registered: 2008-07-07
Posts: 795

Re: Which muscid ?

Thanks Peter. All the other features being in place it definitely looks as if you have a female E. cyanella; you'll certainly know it next time - I don't think it's easily confused with anything else once you're familiar with it. It's probably the most common Muscid to be found so early in the year.

Offline

 

Board footer

Powered by PunBB
© Copyright 2002–2005 Rickard Andersson