Boletus viridiflavus or Aureoboletus auriporus. Common; a polypore. Saint Petersburg, Florida. August. Note: mushroom fly maggots. The Sciaridae are a family of flies, commonly known as dark-winged fungus gnats. Commonly found in moist environments, they are known to be a pest of mushroom farms and are commonly found in household plant pots. This is one of the least studied of the large Diptera families, probably due to the small size of these insects and the difficulty in specific identification. Currently, around 1700 species are described, but an estimated 20,000 species are estimated to be awaiting discovery, mainly in the tropics. More than 600 species are known from Europe.