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This is a female. It does not have male genitalia at the tip of the abdomen. The sparse hairs on the flagellum are normal for a female.

In some species of Chironominae and Orthocladiinae males have female-like antennae with fewer flagellomeres and reduced or absent plume. These species live in harsh habitats and do not form aerial mating swarms.

If your fly has hairy wings, hairs on the membrane near the wingtip and not only on the veins, most of the possibilities are eliminated.

Color patterns can be useful, though as one American specialist puts it "they aren't birds". A good picture can show information about the male terminal appendages. Males of Polypedilum have triangular tergite 8. There is a tendency near Chironomus to develop "frontal tubercles". The shape of the pronotum is useful in some cases.