Diptera.info

Posted by nick upton on 07-06-2010 10:22

Can anyone suggest an ID for this small Corsican Tachinid, Gymnosoma clavatum or rotundatum maybe?

c 8mm 4th June 2010 on Umbel flowers, by mountain stream , 500m in Corsica

Edited by nick upton on 22-11-2010 21:06

Posted by ChrisR on 07-06-2010 11:45

Hmm, it's going to need Theo because they really are very hard to ID - especially from photos. It's a male and it isn't nudifrons but other than that I'm not sure ... even with a specimen they are tricky :)

Posted by nick upton on 07-06-2010 19:37

OK, many thanks Chris. I hope Theo can help get it closer to a species ID. I have more shots of this fly which might reveal crucial bristles etc once I know which angles of view help most!

Posted by ChrisR on 07-06-2010 21:16

With male Gymnosoma it's the genitalia (hard to see at the best of times) and the dusting on the face and dorsal surface of the thorax :)

Posted by nick upton on 07-06-2010 23:08

That's going to be tough... but will check what else I have in case it helps..

Posted by ChrisR on 08-06-2010 00:00

Haha - not half as tough as identifying the darn things :D I occasionally get easy ones but with most I sit here for ages scratching my head and wondering if the dusting really is broad behind the suture ... or whether the hairs on the thorax are erect or recumbent ... they really are horrible :)

Posted by nick upton on 08-06-2010 11:15

I know you love it really.... To add to the horrible challenge, here are the only extra pics that might help. No revealing gentalia images, tho - these were well hidden a t all times, but maybe some clearer images for the head/thorax.

Posted by nick upton on 08-06-2010 11:18

#11

Final image. The only other thing I could do is to crop images to give closer views of key areas if needed.

Edited by nick upton on 08-06-2010 11:19

Posted by ChrisR on 08-06-2010 12:06

#12

Yeah, they've very lovely but I could only really guess at Gymnosoma rotundatum or costatum ... and that's just an educated guess so we need Theo ;)

Posted by nick upton on 08-06-2010 16:35

#13

OK, let's hope Theo can take a look and give the definitive ID (without a specimen of course...).

Posted by nick upton on 22-11-2010 15:04

#14

I know these are next to impossible to be sure of from even clear photos from many angles, but can anyone go further than ChrisR of the ID for this? Is Theo out there?!

Posted by Zeegers on 22-11-2010 17:22

#15

Why not nudifrons ?

It is a male Gymnosoma, so with all standard disclaimers, looks like nudifrons to me.

Theo

Posted by ChrisR on 22-11-2010 18:44

#16

Ahh, yeah I forgot that the undusted parafrontals is only a female character ... but I still don't think that I would have had the confidence to say it was G.nudifrons :D

Posted by nick upton on 22-11-2010 19:05

#17

Many thanks Theo and Chris. As always I'm happy to go along with what I'm told by them that knows, and seems you were right Chris, to say we needed Theo's help on this. I may dig out a couple of other Corsican Tachinid IDs you got close on but not all the way.