What Bug Is That? The guide to Australian insect families.

Logo: What Bug Is That? Logo: Taxonomy Research & Information Network



The Sciaridae are a species-rich, cosmopolitan family of fungus gnats belonging to the superfamily Mycetophiloidea.

The immature stages of Sciaridae are found predominantly in soil, where the larvae of some species form large aggregations. Larvae feed on fungal hyphae, rotting materials including wood, faeces, bird and mammal nests. One species thrives as an inquiline in termite nests ( Austrosciara termitophila ). Certain species breed in the medium of potted indoor plants where little harm is caused, except the irritation of having small flies swarming in 'sealed' air-conditioned buildings. However, certain species of sciarids do cause damage in commercial mushroom cultures, whilst others are pests of greenhouse crops.


The Sciaridae are usually distinguished from other flies in the Mycetophiloidea by the dorsal extensions of the eye, which meet medially (forming an 'eye bridge'). The presence of spurs on the tibia allows differentiation from lestremiine cecidomyiids. Certain soil-dwelling sciarids lack an eye bridge.


The study of Sciaridae is in its infancy in most parts of the world. The Australian fauna is amongst those that are inadequately studied, with only the mushroom pests being at all well known.

  • Sciaridae

  • Sciaridae, female

  • Sciarid (black fungus gnat)

  • Sciaridae with larvae