Picture taken in May, east China (Zhejiang province). It is a small black fly, approx. 3mm in body length. Could it belong to the Anthomyiidae family? Many thanks in advance!
I did a few quick comparisons with some species in Agromyzinae that have been recorded from Zhejiang. I think Ophiomyia maura is most promising . See the BugGuide picture at: https://bugguide....ew/1325111