Thread subject: Diptera.info :: Tachinidae ex pupae, Oct.26, 2006
#1
I've already said goodbye to
Tachinidae until next spring, but now I'm back with images of freshly-emerged (late autumn?) species.
3 specimens, host:
Acronicta sp. (
A. psi or
A. alni, my records are still not too accurate). Size 9mm.
#3
And the head.
(My 1000th post, and it's a Tachinidae

!)
Posted by
Xespok on 26-10-2006 18:16
#4
Somewhat similar to Carcelia sp that I posted a few weeks ago, but with Tachinids lets wait for Chris or Theo.
Posted by
Zeegers on 26-10-2006 21:07
#5
Well, it clearly is Carcelia and with such nice pictures we might even get a full ID (Carcelia is difficult genus).
The vertex is very small, the basicosta yellow, tibia 2 yellow with 1 ad, humeri dark, and the thorax slightly reddish in front of scutellum leading to
Carcelia rasa (male)
The host is suprising:
Carcelia rasa prefers Lymantriidae.
However, crossing over to other families as expection in known for many species in Carcelia.
C. rasa has two generations each year, but this record is late even for the autumn generation.
Theo Zeegers
#6
Thank you so much Theo, even down to a species level ID, I'm really impressed

. Concerning the host, now I have some doubts. I fed only 2 spp. of
Lymantriidae, L. monacha (infested by a parasitic wasp, emerged on July 14), and
C. pudibunda (collected on Sept. 03 on Salix, no articulate further records, but I can check if its pupa is present, it's rather easy to recognize, and then double-check to maybe exclude
Acronicta, I fed many of them and the majority was infested, a common case for solitary caterpillars in autumn).
Posted by
ChrisR on 26-10-2006 23:16
#7
I'm impressed too - I am not sure I'd like to split
rasa,
bombylans and
puberula without measuring the frons with with a graticule

Here it is a very rare species and we have been finding more
bombylans than
rasa in recent years

#8
Thanks for your remark Chris - and some more on host: I remembered also a
Leucoma salicis (collected on August 01, there's a remark 'immediately started preparing to pupate' on it, I should check more of my (loose) notes to find out what its fate actually was).
Posted by
crex on 27-10-2006 09:04
#9
I can't stop being amazed by the quality of your photos Black! Could you please reveal exactly what equipment you use and what settings for camera, lens, flash ... perhaps in
the macro lens thread, in a new thread or in a PM to me if you don't want it to be public!? I haven't been able to take photos with such good lighting, DOF or overall sharpness. I know that most photos are taken in your kitchen, but nontheless that doesn't make the photos less breathtaking. Thanx in advance from a true fan
If Nikita wants to share his equipment too I woudn't mind. I'm thinking of his nice photos of the small Dolichopodidae etc in the wild.
Posted by
Zeegers on 27-10-2006 09:33
#10
I consulted H.-P. Tschorsnig (Stuttgart), he is the real expert in Tachinidae.
The chances of C. rasa being bred from Acronicta are in his opinion very small indeed, because Acronicta has been bred many many times and C. rasa never occurred (C. atricosta did once).
There is a small chance that the species might be Senometopia separata.
On the other hand, given the new info by Black, there is the possibility that a Lymantriid was the host after all !
My personal view is that the second option is the most likely.
if th specimen was collected, and/of if we can get a photo of the middle leg in frontal view or back view, we can get to a really positive ID.
I know, you make such great pictures, and then I start complaining about not being able to see the underside of the middel tibia!
Theo Zeegers
Posted by
ChrisR on 27-10-2006 09:59
#11
It's the unwritten rule of diptera identification from photos - "there's always 1 more angle to photograph"!

#12
Thanks to all for your remarks. 2 crex: will inform soon - no secrets. 2 Theo Zeegers: specimens are collected and still alive, will post mid tibia image(s) soon, and it's really nice to have such a comment from Hans-Peter Tschorsnig.
#13
Here's some views of the right tibia II of a mounted fly - please let me know if that's enough Theo.
Posted by
Zeegers on 28-10-2006 13:37
#14
thanks Black,
The middle picture settles it: there is clearly a ventral bristle, in retrospect we could have seen it all along (I noticed it, however, perspective can be very tricky in pictures so I wanted to be very sure).
Implying: Carcelia, not Senometopia
and therefore:
Carcelia rasa it is.
Any news on the host ?
Theo
Posted by
ChrisR on 28-10-2006 15:54
#15
If it is a male then the genitalia are usually quite distinctive - to add weight to the identification

While it is soft just hook out his 'bits' with a fine pin and let them dry. I have some line drawings here somewhere that I can send to you if you'd like to give it a try

#16
Many thanks Theo and Chris. As regards the host, now I'm sure it was
Calliteara pudibunda. I will check if I got any males (two specimens are still alive).
Posted by
ChrisR on 29-10-2006 10:29
#17
When you find a male to examine just download the
Carcelia article from here
http://tachinidae...ifrons.pdf 
It doesn't cover all European species but here we are primarily just trying to back-up the suggestion that it is
C.rasa, so if the figures look the same as your specimen then it adds weight to the identification

#18
OK thanks again Chris.
#19
Today I've got the fourth fly. The smallest of the four is 8mm, and they all are females.
Posted by
ChrisR on 29-10-2006 20:06
#20
Ahh, it is normal for all flies to be the same sex if they are from the same host.

The frons is unusually narrow so with nothing more to work on Theo's
C.rasa seems the best bet.
