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Manitoba Museum

Flies (Diptera)

Dark-winged Fungus Gnats


Also called Mushroom Flies, this family occurs on all continents except Antarctica. Most species are rarely noticed but some occasionally move in masses, for purposes that are poorly understood. Larvae are major decomposers, feeding on decaying plant material, animal feces, fungus, or plant roots. They can be pests in greenhouses, and of commercially grown mushrooms. Adults sometimes feed on flower nectar, but are not significant pollinators.

Representative Genera and Species:


Pollinator Life Cycle:

They have four life stages: egg, larva, pupa, and adult. In some species, a cocoon is shared by several larvae that develop, mate, and lay eggs all while remaining inside. In other species, the offspring’s sex is controlled by the mother, with some producing all females, and others only males.

Rarity Status:

The status of Canadian species has not yet been assessed, and none are legally protected.

Physical Appearance:

These small (1-11 mm long), delicate flies are similar to Fungus Gnats. Colouration is black, brown, or yellowish. Their head is usually higher than long, and their kidney-shaped eyes wrap around their 14-segmented antennae. They usually have gray or brown, clouded wings. Identification to species is based mainly on inspection of adult males.

Pollinator Habitat:

They are often found in flowerpots and other moist places, where fungus often grows: forests, swamps, and meadows. Some live in extreme habitats (Antarctic islands, mountains and deserts), caves, animal burrows, and bird nests. Adults are often in foliage, while larvae tend to live on fungi, decaying vegetation, plant roots, or under bark.

Canadian Distribution:

  • Alberta
  • British Columbia
  • Manitoba
  • New Brunswick
  • Newfoundland/Labrador
  • Northwest Territories
  • Nova Scotia
  • Ontario
  • Quebec
  • Saskatchewan
  • Yukon

Prairie Types:

  • Fescue Prairie
  • Mixed Grass Prairie
  • Tall Grass Prairie
Dark-winged Fungus Gnats