Who is here? 1 guest(s)
 Tachinid?
|
|
| John Webley |
Posted on 21-08-2006 10:53
|
|
Member Location: Posts: 21 Joined: 14.08.06 |
I had this noted as a hover fly but looking at my books I have doubts and it looks very similar to the one in Stephen's recent thread. Can someone help please. It was taken in May last year in Kent UK. Thanks, John |
 |
|
| John Webley |
Posted on 21-08-2006 10:55
|
|
Member Location: Posts: 21 Joined: 14.08.06 |
Done it again. Here's the image |
|
|
|
| Zeegers |
Posted on 21-08-2006 12:00
|
|
Member Location: Posts: 18446 Joined: 21.07.04 |
Any indication of size ? It is either Dufouria (which is not so common), or a special species of Macquartia. Tachinidae, in any case My money is on the first Theo Zeegers |
|
|
|
| John Webley |
Posted on 21-08-2006 12:48
|
|
Member Location: Posts: 21 Joined: 14.08.06 |
Sorry to be vague on size but my recollection is that was reasonably large. It is sitting on a bramble leaf which gives some idea. It would be helpful to know what identifies for sure as Tachinidae. Thanks, John |
|
|
|
| Zeegers |
Posted on 21-08-2006 13:43
|
|
Member Location: Posts: 18446 Joined: 21.07.04 |
Dear John, Well, there is no general rule how to recognize a Tachinid. So let me give some rules of thumb (to all of which exceptions exist !) -1) any really spiny fly is a Tachinid (but the reverse is NOT true) -2) more general, follow the following program: * is my fly a calyptrae ? Calyptrae should be large, thorax should have distinct transverse suture. YES -> * vein M has a distinct bend. (no Muscidae/ Anthomyiidae) YES -> * postscutellum strongly swollen (difficult to see) arista generally bare eyes never trafficlight-red abdomen often with strong bristles species not metallic (with 2 exceptions) YES ? -> 99 % Tachinidae Have a look at the gallery, Colyer and Hammond or whatever general textbook on diptera. It still is difficult. Start and get experience, you will learn Good luck Theo Zeegers |
|
|
|
| ChrisR |
Posted on 21-08-2006 14:15
|
 Administrator Location: Posts: 7699 Joined: 12.07.04 |
Yeah, if you catch a lot of calyptrate flies and examine them for a subscutellum you gradually get a 'feel' for what makes a tachinid... the big problem is the answer to the question "what makes a rhinophorid?!"  |
|
|
|
| John Webley |
Posted on 21-08-2006 15:03
|
|
Member Location: Posts: 21 Joined: 14.08.06 |
Theo, thanks a lot for your help and additional guidance. Much appreciated. Not able to fully appreciate the reference to Rhinophorids yet but may get there one day. John |
|
|
|
| Zeegers |
Posted on 22-08-2006 18:37
|
|
Member Location: Posts: 18446 Joined: 21.07.04 |
The answer to the Rhinophorid question is simple but very unscientific: there are only a few genera and so you learn the genera, recognize the genera and therefore know they should be Rhinophorids. But I agree with Chris, Frauenfeldia (Rhinophoridae) could easily pass as Tachinid. Theo |
|
|
|
| John Webley |
Posted on 23-08-2006 08:23
|
|
Member Location: Posts: 21 Joined: 14.08.06 |
Thanks Theo, it all helps. |
|
|
|
| Jump to Forum: |
