Introduction to Milichiidae

The Milichiidae (Diptera, Schizophora) are small, mostly black acalyptrate flies. The family contains about 390 extant and 10 fossil species in 18 genera and is worldwide in distribution. In Europe about 35 species occur. Navigate the classification to find taxon pages for all genera and species!

The behavior of several species of Milichiidae is very specialized. For example, in some species the adults are myrmecophilous (= ant-loving), whilst in some others they are kleptoparasitic, feeding on the prey of spiders or predaceous insects. Find out more on the biology page.

The habitats of Milichiidae are diverse. Adults can be collected in open landscapes, such as steppes or meadows, in wadis, at the edges of forests, inside forests, in the forest canopy, in stables or houses, or even in caves. However, they do not seem to be attracted to coastal habitats or to other places near water.

The Milichiidae are divided into three subfamilies, Madizinae, Milichiinae, and Phyllomyzinae. Find out more about the phylogeny of the family.

Common names

Common names are only rarely cited for Milichiidae and seem to be more of an invention of the author than a commonly used name. The English term "filth flies", for example, which is sometimes used for Milichiidae, was introduced by Sabrosky (1959) in the title of a paper about the genus Meoneura, which now belongs to the family Carnidae. Sabrosky probably used the general expression "filth fly" to describe the biology rather than intending the term to be a common name for the family Milichiidae. The term "filth flies" is generally used for several different taxa associated with 'filth'.

Since people keep stumbling over the name 'Milichiidae, I herewith introduce a new english common name: "freeloader flies". The name refers to the biology of Milichiidae. Definitions for 'freeloader' are: 'someone who takes advantage of the generosity of others' ( or 'one who depends on another for support without reciprocating' ( 

Other 'rare' common names:

  • Nistfliegen (German)
  • Futterdiebsfliegen (German, see Tschirnhaus 2008)
  • sefliegen (German). This term is nowadays used for the family Piophilidae.
  • Blatthornfliege (German, only for genus Phyllomyza)
  • Sprickflugor (Swedish, Hedström 1994)
  • ?Vuilvliegen (Dutch)
  • Pakosztoslegyek (Hungarian)
  • ?Kurokobae (Japanese)
  • Tumšmušas (Latvian, Karpa 2008)

Do you know the name for Milichiidae in your language? If yes, tell us by adding a comment.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith