The ones I fish are black gnat emergers, which look like a big midge. I tie them in size 12 and 10. I usually just go to thread to save time on the abdomen but a fine quill would be better if you could get the black/white segment effect.
Even when they are tuned into emergers I still seem to do well with a bead-head black bugger, go figure.
I'm certainly no entomologist but the gnats are everywhere right now.