Fungus Gnat
Sciaridae or Mycetophilidae (Family)
- Order & Family
- Order Diptera, Family Sciaridae or Mycetophilidae
- Size
- 2-8 mm (adults), larvae are typically a bit smaller.
Natural Habitat
Damp, moist environments rich in decaying organic matter, often found near houseplants or potted plants with overwatered soil. Indoors, they thrive in bathrooms, kitchens, and basements.
Diet & Feeding
Larvae primarily feed on fungi, decaying plant matter, and sometimes plant roots (especially delicate seedlings). Adult fungus gnats do not feed and live only to reproduce.
Behavior Patterns
Adults are weak fliers and are often seen hovering around houseplants or windows. They are most active during dusk and dawn. Females lay eggs in moist soil, and larvae develop within the soil over 2-3 weeks before pupating and emerging as adults. Their life cycle is relatively short, around 3-4 weeks.
Risks & Benefits
Potential risks include damage to plant roots, especially seedlings, leading to stunted growth or wilting. They can be a nuisance indoors. They are generally not harmful to humans or pets. Benefits are limited in a household setting, but in nature, their larvae help in decomposition processes by feeding on decaying organic matter and fungi.