Frons and body hairs are snowy white on your example. The frons on macrocera (I have just checked a specimen) are really dark yellow-brown. I don't know why it is, but sometimes from several feet away you can see big mildew-like splotches of white on the thorax and sides of the abdomen on albipilosa, and sometimes they look like your example. As I say, I tend to identify them by date, and here in Arkansas that means macrocera all summer long till about 20 August, then albipilosa starting about the first of September.

I find the two species tricky to separate. Sometimes albipilosa is very woolly and obvious, sometimes it isn't. Here in Arkansas macrocera is essentially gone by the middle of August, then after a few week's gap albipilosa appears. Try looking at the fine hairs covering the thorax and body. I believe they should be yellowish on macrocera, and white on albipilosa.