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Hello together,

on the 03.09.2008 I took a caterpillar of Pieris rapae with me (Norderstedt, West Germany) and documentated the death of the caterpillar and the birth of two different flies. If you are intrested, the whole story you find under http://insektenfotos.de/forum/thread.php?threadid=19893&sid=0cc9b575c4a226716c959b56082f60f9

The last secrets are the names of the flies. From this one I can show male and female flie-pictures in all situations.

Who knows this one? I think, this ist the female one.

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Hi,

I think the caterpillar belongs to the species Lacanobia oleracea of the family Noctuidae.

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And I think, this is the male flie.

Rui, thanks a lot, that looks very good.

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A different flie from the same caterpillar ist this one.

I would be very happy if it is possible to get the names.

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Sorry, is nobody able to give me any informations about my flies?:|

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Hi Kirsten,

The specimens are still teneral and not all necessary details are visible, but my guess would be: Bactromyia aurulenta.

All the best,

Jaakko

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Just wanted to say very well done for getting such an excellent sequence of photographs.

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I agree with Jaakko that Bactromyia is a likely candidate.
Have they been collected ?
More news on the host ?


Theo

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Good evening Jaakko,

I'm very happy to get an answer, sorry, my English ist very poor, I hope I understood it right.

You think about Bactromyia aurulenta, but normaly you like to see more details. I have a nice "upskirtphoto" for you:) and one of the face. This photos belongs to the second flie.

Doe you think that this three flies are all the same species? For me the third one looks so different.

Thanks Nigel (getting red);)

Hi Theo, no, I don't have them anymore. One ist been killed by a Vespula vulgaris as you can see in the link of my first posting. I'm glad, that you agree with Jaakko. Maybe you also see more on the next photos. If not, please tell me with part of the flie you need.

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face

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face of the flie on the third picture

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and also one photo of an sliping lava and a very fresh pupa

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The eyes are distinctly hairy in the newest pic.
So I'm starting to doubt Bactromyia.
Alternative is Phryxe nemea with similar golden dusting on vertex.


Theo

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Yes, I'm sure you're right Theo. If I remember right, B. aurulenta also lets the host pupate.

All the best,

Jaakko

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Thanks a lot Jaakko and Theo, makes me very happy that my flies have names now.

May I ask, why the third flie looks so different for me? The long neck is to see on every picture and it did not get more colour after hours. It also has more hairs between the eyes.

I thought that No. 1 is a male one and the others both are female. Is this correct?

Sorry to disturb you with so many questions, but I like to understand all what I've seen.

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Hello again,

Always good to ask questions to learn new, so don't apologize! The coloration and other funny features on the third fly are also due to the fact that the fly has recently emerged from the pupa. It might take surprisingly long for some individuals to develop final colour and appearance. These flies (as well as others like them) use so called ptinal pouch (not sure what the real term is) to crack open the puparium. This pouch retracts, leaving a ptinal suture. You can see partly retracted pouch on the fly 3, making the frons also look wider. I think all the flies are females.

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Dear Jaakko,

thanks a lot for your detailed informations, very interesting. All this is like a new exciting world for me and I wonder every day like a child.