asmith33's picture

Diptera species (added via Android)

Observed: 30th November 2012 By: asmith33asmith33’s reputation in Invertebrates
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Description:

This is a line drawing of an unidentified diptera wing. unfortunately I have no good photos of the specimen itself but the drawing is very representative. The bristles along the wing margin are hinged and often appear within the wing area, forming an 'eye-lash' appearance.

Identifications
Species interactions

No interactions present.

Comments

Martin Harvey's picture

intriguing

That looks like a good illustration, but I can't find a fly family that matches it entirely - my first thought was the dance-flies in family Empididae but can't find anything quite like your drawing.

Are there any other clues available about the rest of the fly - shape, size, colour?

There is a good website that illustrates insect wings, but again I can't find a good match for yours at the moment:
http://www.drawwing.org/insects/diptera

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Entomologist and biological recorder

John Bratton's picture

Is it definitely a fly and

Is it definitely a fly and not a small hymenopteran? The venation looks odd for a fly, and hairy wing margins are not so unusual among small parasitic wasps.

asmith33's picture

Added notes

Thanks for taking the time to look at this.

John it is definitely a fly. Martin we have been using Drawwing to try and aid us but we have not succeeded.

Here are a few more notes:

- Very small flies (2mm)
-Bristles found all over body
-Likely to be Acalypterate
> Halteres obvious
> Vibrasse absent
> No transverse suturre on dorsal side of thorax.
-Antennae with less than 5 segments- arista dorsal
-Possibly Sphaeroceridae
> Hind tarsal segment swollen (almost like a spur)
> venation incomplete

Martin Harvey's picture

Diptera

Hmmm, the swollen hind tarsal segment does fit with Sphaeroceridae, but that family has vibrissae (strong bristles at the mouth edge).

I'm afraid I'm stuck with this one. Would be great to see the fly itself, even if it's not a clear photo.

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Entomologist and biological recorder

asmith33's picture

photos to come

I have taken some down the microscope and will try and upload them ASAP

John Bratton's picture

I've looked through the RES

I've looked through the RES key to Sphaeroceridae (Pitkin 1988) and the best match is Trachyopella, figs 237 and 238. Fig. 237, T. leucoptera, is the better fit, having quite a short and broad wing. It has vein 2 meeting the costa well past half way along the wing, and vein 3 meeting it nearly at the wing tip. Veins 4 and 5 are in approximately the right place and don't reach the wing margin. But it doesn't have your rather meandering cross vein between 4 and 3, nor any sign of a faint vein 6, nor a fringe of hairs in an indentation. Not all Trachyopella species have their wings illustrated, so don't take this to be a definite identification, even to genus.

Can you put up a photo of the whole fly? I often find they photograph best submerged in alcohol (70%) rather than dry. If you can put it under a dissection microscope, you can get a passable picture by just holding the camera against the eyepiece.

John

asmith33's picture

Better photos will come

Better photos will come soon....

John Bratton's picture

Bernard Verdcourt of Kew

Bernard Verdcourt of Kew Botanic Gardens wrote an article called “Wingate's Durham Diptera (1906) still useful” in EMM in 2000: “On 17 July 1999 I collected from a vast cloud of small flies over horse dung at Henlow Common, Bedfordshire. .... Two had a very distinctive arrangement of hairs on the rear margin of the wings and bent back across the wing. .... I was puzzled to find no mention of these peculiar structures in Pitkin (1988). .... At this point I looked in Wingate and immediately found them on p. 380 ... leading to Limosina acutangula Ztt, now known as Coproica acutangula.” He also shows an electronmicrograph of the wing - just like yours.

Martin Harvey's picture

result!

Thanks for that John, excellent detective work :-)

I used to know the late Bernard Verdcourt, he helped me when I was starting to learn a few more insects beyond the Lepidoptera - a great enthusiast.

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Entomologist and biological recorder

asmith33's picture

Great thank you so much John!

Great thank you so much John! and everyone else who has contributed, it is very much appreciated. I have just read that it is only the males that have the fringe of hairs.

Many thanks