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Hello,

here I am rather sure with the genus Gymnosoma. And I know that the determination of species by photo is nearly impossible. But is a good suggestion possible here? And is it a female or a male and how do I distinguish the genders?

I found it end of june between an old vineyard and a forest near the river Ahr in western germany.

Thanks,
Michael

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Yes, it is a male Gymnosoma, it is slightly atypical so no ID here.


Theo

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Thank you Theo. How do you distinguish males and females here (or in Tachinidae in general)?

Michael

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Any real observation need to check the genitalia

In this case, it is easy:
thorax dusted anterior -> male
completely black -> female

Rules of thumb:
* males have vertex narrower than females
* females have 2 pairs of proclinate orbital setae on frons
* anything with long pulvilli is male

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Thank you again, Theo.

Greetings,
Michael