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Fungus Gnat

Fungus Gnat (Dark-Winged):

General Description

Credit: Peter Rühr

Credit: James Lindsey

  • Fungus gnats are distinguished from fruit flies because of their darker
  • They are usually less than 5 mm long and short-lived gnats.
  • These flies are sometimes confused with drain flies.
  • The adults are 2–8 mm long.
  • Larvae are slender and lack legs.
  • Larvae are white (except for a black head), lender, and lack legs.
  • The skin of the larva is slightly transparent so the contents of the gut are visible.

Life Cycle and Common Characteristics

  • Fungus gnats are the most common houseplant
  • They are found in wet plant soil, in sewer areas, and in household
  • They are weak fliers and are seen walking rapidly over plants and soil, rather than flying.
  • Fungus gnat larvae usually are located in the top 5-7 cm of the growing medium, depending on moisture
  • They feed on fungi, algae, decaying plant matter, and plant
  • Larvae develop rapidly and are fully grown in 2-3
  • Larvae pupate from July to August, in or on the growing
  • Adults emerge about one week
  • Adults are weak fliers and fly in erratic
  • In homes, they usually are seen in the near vicinity of an infested
  • Adult life span is 5-10 days.
  • Females may lay up to 200 transparent eggs into the cracks and crevices of growing
  • Adults do not bite but may drink water residing on plant leaves and/or on the surface of growing media

Damages, Economical and Medical Implications

  • Fungus gnats are nuisance insect when present in noticeable numbers, but the adults are harmless and do not
  • Adults are occasionally pollinatorsof plants and carriers of mushroom spores.
  • Adults also may carry diseases such as pythium(which causes “damping-off” to kill seedlings) on their feet.
  • The gnats may be quite annoying to humans by flying into their faces, eyes, and noses, both indoors and outdoors. This is because adults are attracted to CO2)
  • Larvaefeed on fungi growing on soil, helping in the decomposition of organic matter.
  • Larvae tunnel into the stalks of the mushrooms and causing mushrooms to become brown and leathery.
  • Fungus gnats are usually associated with the fungus and algae growths found around air conditioning pipes at which the moisture and improper drainage of the air conditioning system may produce asignificant amounts of fungus and algae that attract gnat flies inside homes and annoy Thus, when gnat fly problem occurred you must check indoor houseplants and air conditioning system.