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

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The Perissommatidae is a species-poor, but biogeographically interesting, family of small Lower Diptera.

Adult Perissomma are found in winter months in forested areas, including non-native pine plantations. The immature stages of Perissomma have been found in liquescent fungi; pupation occurs within the larval skin. The larvae of P. fuscum have been found in Boletus fungi. Larvae presumed to be of P. mcalpinei have been collected from moist leaf litter.


Adults are distinguished by the unique division of the eyes into ventral and dorsal sections, and by a characteristic wing venation in which R2 is forked and R2 ends in the costa.


The five extant species are all placed in the genus Perissomma which is found in Chile and south-eastern Australia. Three species in two further genera are known from fossils from the Jurassic of the Northern Hemisphere.

  • Perissommatidae