Diptera.info

Posted by jorgemotalmeida on 21-11-2006 12:50

HI

* locality - Silgueiros - Viseu - PORTUGAL
* date - 14.11.2006
* size - 4 mm (small fly)
* habitat - open land
* substrate - granite

this fly was always moving and the wings moved a lot. I think this could be a Rhinophoridae by the small size, and very spiny (?) legs? Tachinidae don?t have so spiny legs? or is it not true? which is the best character to distinguish between Tachinidae / Rhinophoridae apart the size (rhino flies are, in general, much smaller than tachinid flies).

One sure: this is a Calyptrate fly. :) We can see upper calpypter.

but see this one issue:

Most of the Muscomorpha are further subdivided into the Acalyptratae and Calyptratae based on whether or not they have a calypter (a wing flap that extends over the halteres)."

in wikipedia..

it is funny to see then in http://www.ento.csiro.au/biology/fly/fly.html that

Rhagadolyra magnicornis is an Acalyptrate fly and HAS 1 calypter! (one, at least visible). I know in Biology, there are always exceptions. But they could choice a better model to avoid confusion... is Rhagadolyra magnicornis an exception? Or the division Acalyptrate / Calyprata is no sense now...

"The name refers to the lack of calypters in the members of this group of flies." in glossary of diptera... it must be important to note that there are exceptions... and why, if possible.
I cannot get to find any more clues about characters of acalyptrate flies.. please give me more info. Thank you.

Edited by jorgemotalmeida on 10-04-2010 03:39

Posted by jorgemotalmeida on 21-11-2006 20:57

Zeegers wrote:
Hi Jorge,

And some Tachinidae are very small as well !
Remember, Rhinophoridae has relatively small calyptrae.
So this must be Tachinidae.
Actually, it is a typical member of the tribe Wagneriini.
But which one (Wagneria, Periscepsia, Ramonda...)??

Theo Zeegers

Hi theo

tell me which kind of photo you desire :D to get off some doubts about genus. :) I will try to take another photos. This fly is very recognizable and easy to spot. But now it is raining :(

Posted by Zeegers on 21-11-2006 21:37

Ok, I had a very good look.
and I can see 3 humeral bristles in a triangle and small discal setae on the tergite 4, but not on 3, which would imply Periscepsia.
Periscepsia carbonaria is by far the most common species and can be found very late in autumn.
So, that would be my 95% guess.
Beware, it is a lot to ask to give an ID in such a difficult group, not matter how good the pictures !

Theo

Posted by jorgemotalmeida on 22-11-2006 01:20

Zeegers wrote:
Ok, I had a very good look.
and I can see 3 humeral bristles in a triangle and small discal setae on the tergite 4, but not on 3, which would imply Periscepsia.
Periscepsia carbonaria is by far the most common species and can be found very late in autumn.
So, that would be my 95% guess.
Beware, it is a lot to ask to give an ID in such a difficult group, not matter how good the pictures !

Theo

theo.... I see a petiole.. in wing... :S

"Lastly, the common rhinophorids have a large petiole on the wing and an angled vein-M - as on this picture of Paykullia maculata. This species also has very distinctive shading along the wing veins, which makes it quite easy to identify."
...
http://tachinidae.org.uk/site/rhino.php

but... the M vein is gently curved... so Tachinidae? or is this an exception?
ok. I understood about calypters that are bigger in tachinidae but not easy to say sometimes, because it is relative...

i cannot see those humeral bristles.. the wing seems to hide above hind tibia..

Thank you!