Also known as Frit Flies, Stem-miner Flies and Eye Gnats. ~280 species in North America, ~3,000 worldwide.

                    Most species are black or yellow. The ocellar triangle is usually large and shiny.

                    Grass flies are common in meadows and grassy areas, though they may be found in a variety of habitats

                    In most species larvae feed on grass stems of the families Poaceae, Cyperaceae, and Typhaceae. Some
                    are serious pests of cereals. Some species are saprophages, scavengers, parasites, or predators.

                    Some species are attracted to the eyes (the so-called 'eye gnats,' vectors of yaws and pink eye).
                    Some are pollinators of orchids or Araceae flowers.