you must be more imaginative than me :-)

am thinking this is a male

of Poecilominettia I can find but didn't see anything suggesting that the black spot of P. puncticeps was sexually dimorphic. None of the 6 species I can find descriptions of really fit this particular fly (macula, ordinaria, puncticeps, punctifer, slossonae, and valida). P. ordinaria comes the closest because of the infuscated crossveins (weak in this individual but still darker than the other veins). Where P. ordinaria doesn't fit this individual is in the hairs on the face: "One of the setulae near upper extremity of the series on side of face strikingly longer and stronger than the others; arista almost bare" (Malloch & McAtee). Those setae are visible in the BugGuide posts below

I'll try to find out

Sometimes I think it is almost better not to find these citations than to try to use them...
Re: sex differences, abdominal venters are hard to get in live shots but nice laterals aren't (just like humans!). Below is why your guy looks male to me. Incidentally, your awesome shots ought to be good enough for species ID, or I'm Charles Darwin.

getting me to look at this one again and for the compliment on the photos. I couldn't agree more about the old papers; the older they are, the more nebulous their descriptions.
I think you're right about this one being a male but I don't see any way forward to a species ID with the papers I can find. I guess we'll have to start referring to you as Mr. Darwin :-)