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Hello,

I think it's a male Bithia ?
But I can't choose between Bithia demotica and Bithia modesta. Maybe even Bithia immaculata, I find that T2 is not shaded all the way to the posterior margin, but the dark spot is really very close to the posterior margin so I don't know if that matters


I have other pictures if needed


Jessica Joachim : France : Serviès : 81220 : 15/06/2024
Altitude : 295 m - Taille : 10 mm environ
Réf. : 353815

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If you take the alternative with excavation of T1+2 not extending to posterior margin you end up at a group of species with wider frons. As I interpret the keys it can't be Bithia immaculata because the abdomen is not immaculate. I can not distinguish demotica, modesta, and proletaria. Cerretti's key says distal half of scutellum yellow for modesta and scutellum almost entirely yellow for proletaria. Your fly might fit either alternative.

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Thank you so much. I said immaculata but I rather wanted to say acanthophora.

I didn't know Bithia proletaria. It's not noted from France, but from Italy, it's not very far.

What about the color of the scutellum of demotica ? Is this key accessible?

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Cerretti's book is I tachinidi della fauna italiana (Diptera Tachinidae).

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Thank you very much !

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Demotica and modesta can not be distinguushed on externel features.

So no wonder you couldn't decide ....


Theo

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Thank you very much Theo !
If I am not mistaken, we can still distinguish the two species with the females? If the palps are black it is modesta, on the other hand if they are yellow it can be both species. But for this one it does not count since it is a male :)