An extremely minute fly, about 2mm in length, that landed on my desk. I was lucky to have it stay put long enough for me to take a picture, and even luckier to have it spread its wings briefly. While the wings were not dark, it fit the general description for dark-winged fungus gnats (family Sciaridae) given in Borror and White
(1), particularly the diagram of the wing veins on p. 271. Confirmation that its a Sciarid or other opinions would be appreciated.