Ditomyiidae

Ditomyiidae can be distinguished from other fungus gnat families by the following combination of characters: eyes do not meet above the antennae (separating them from Sciaridae); wing venation with distinct patterns of the radial sector; and male terminalia with characteristic symmetrical gonostyli. The family is most readily separated from Mycetophilidae sensu stricto and related families (Keroplatidae, Bolitophilidae, Diadociidae) by detailed examination of wing venation, antennal structure, and male genitalia. Specimens of Ditomyia macroptera, the largest European species, reach 8 mm in body length with uniformly smoky wings and dark brown to blackish coloration.

Associated with forested environments, particularly mature woodlands containing bracket fungi. Documented rearing records indicate development within fruiting bodies of polypore fungi. Specific habitat records for Ditomyia macroptera include mountain forests at elevations around 850 m and old orchards.

Worldwide except Afrotropical Region. Primary diversity centers: Australasian and Neotropical realms. Europe: two genera only—Ditomyia (Central Europe) and Symmerus (Northern Europe, endemic to Palaearctic). Documented European countries include Germany, Poland, Czech Republic, Slovak Republic, Italy, Bulgaria, France, Denmark, Norway, and Sweden. A questionable record exists from Sakhalin Island (Russia).

Mycophagy (fungus-feeding). Larvae develop within fruiting bodies of bracket fungi (Polyporaceae). Documented host fungi include Phellinus igniarius and Phellinus alni.

• Phellinus igniarius - larval development siteOriginal description record
• Phellinus alni - larval development siteBulgarian rearing record

Complete metamorphosis with egg, larva, pupa, and adult stages. Larvae develop within fruiting bodies of bracket fungi. Adults emerge from fungal hosts. Rearing events are exceptionally rare; only two documented rearing events for Ditomyia macroptera in the 150+ years since its description.

Decomposer; contributes to nutrient cycling in forest ecosystems through association with wood-decaying fungi.

Minimal direct interaction with humans. Ditomyia macroptera is considered critically endangered in the Czech Republic due to habitat loss and extreme rarity.

• MycetophilidaeHistorically included Ditomyiidae as a subfamily; separated based on wing venation, antennal structure, and male genitalia. Family-level distinction requires expert examination.
• SciaridaeSimilar habitus and habitat; distinguished by contiguous eyes above antennae in Sciaridae versus separated eyes in Ditomyiidae.
• KeroplatidaeRelated fungus gnat family split from Mycetophilidae sensu lato; requires detailed morphological examination for separation.

• fungus gnats
• mycophagy
• forest insects
• rare species
• Europe
• Australasia
• Neotropics

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
• An elegant Eocene fly | Beetles In The Bush
• New European records of Ditomyia macroptera Winnertz (Diptera: Ditomyiidae) with notes on its distribution
• Figure 2 from: Kurina O, Chandler P (2018) New European records of Ditomyia macroptera Winnertz (Diptera: Ditomyiidae) with notes on its distribution. Biodiversity Data Journal 6: e24857. https://doi.org/10.3897/BDJ.6.e24857
• Figure 1 from: Kurina O, Chandler P (2018) New European records of Ditomyia macroptera Winnertz (Diptera: Ditomyiidae) with notes on its distribution. Biodiversity Data Journal 6: e24857. https://doi.org/10.3897/BDJ.6.e24857
• Figure 3 from: Kurina O, Chandler P (2018) New European records of Ditomyia macroptera Winnertz (Diptera: Ditomyiidae) with notes on its distribution. Biodiversity Data Journal 6: e24857. https://doi.org/10.3897/BDJ.6.e24857