Fungus gnat

Fungus gnats are small, dark, short-lived flies, of the families Sciaridae, Diadocidiidae, Ditomyiidae, Keroplatidae, Bolitophilidae and Mycetophilidae (order Diptera), sometimes placed in the superfamily Mycetophiloidea, whose larvae feed on plant roots or fungi and aid in the decomposition of organic matter. The adults are 2-5 mm long and are important pollinators that can help spread mushroom spores as well as plant pollen.