---

L. strigilatum should have 10 ad on the hindtibia....and I don't think I can see them.
Because it is a female Anthomyiidae, it will be difficult, but lets try ..

First we have to know if we are really dealing with Lasiomma.
So could you check if there are very little hairs present on the eyes and you can see them the best, with a black or dark background behind the fly, under your microscoop.
And then you have to check if there are little hairs present on the Costa on ventral side along the whole length (little hairs beneeth the stronger costal hairs)....mostly difficult to see.
If not.......we have a problem :)

Personally, I am more thinking about L. seminitidum.

Johanna