Looks like Delia but the wing is darkened along the costal margin like some members in Pallopteridae family. Picture taken in July in east China (Zhejiang province). Many thanks in advance.
I think it is a Muscidae: anal vein appears incomplete; the frons looks more like Muscidae than Anthomyiidae; the nearly bare space between dorsocentrals, without strong acrostichal setulae, is more typical of Muscidae.