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Hello

A dozen of Mycetophilidae flying around a young group of Pleurotus ostreatus. Sometimes landing, to lay an egg, I presume
My pictures "in situ" are not good.
But I've picked the mushrooms (of course), and one (not too damaged, though a bit crushed) of these gnats

I believe this is one of the Mycetophilinae subfamilly (Am I wrong?)

I used this document to try to go to genera.
From the 65 characters listed, I've only checked 18:
4, 16-18, 24-32, 39, 52, 54, 58, 60

Only one genera almost fully matches these characters : Allodia (at least 3 or 4 non matching for other genera)

The only non matching character for Allodia is:
M stem (0) weak; (1) distinct
I may have misunderstood the meaning:
It seems distinct to me, but it's weekier than the veins above it...

I'm not at ease with the thorax side parts. The last 3 pictures may help, I guess... but don't help me much!


Anonyme : France : Versailles : 78000 : 20/11/2020
Altitude : 170 m - Taille : 6 mm
Réf. : 270991


Anonyme : France : Versailles : 78000 : 20/11/2020
Altitude : 170 m - Taille : 6 mm
Réf. : 270993


Anonyme : France : Versailles : 78000 : 20/11/2020
Altitude : 170 m - Taille : 6 mm
Réf. : 270994



Anonyme : France : Versailles : 78000 : 20/11/2020
Altitude : 170 m - Taille : 6 mm
Réf. : 271105



Anonyme : France : Versailles : 78000 : 20/11/2020
Altitude : 170 m - Taille : 6 mm
Réf. : 271106

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If the left top image on the fourth picture is of the innerside of the hind tibia it will be Brevicornu. Anyway, for full ID microscopic examination will be necessary.

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Thanks for the reply.

[edit: if someone has read my initial reply: oops. If thought Brevicornu was a species...!!!]

I don't know which tibia, nor which side this was.

Now, I still have the fly under my microscope. (and one of the hind legs is separated from the 5 other legs, mixed together. I can have a closer look at it... But I don't know what to look for!)

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The hind les will be the largest legs. The posterior side of the hind tibia (where the femur usually appears to be concave) has at least one, often several, sometimes many short setulae (which stand out from the microsetae) on the apical half. The more of such setae are present, the higher up the tibia they reach.