Pseudacteon formicarum is a kind of parasitic species of flies from the family of Phoridae of the subfamily Metopininae.
Pseudacteon formicarum is found in Europe,[1] [2] and is parasitic on the ants Lasius alienus, Lasius niger, Lasius emarginatus, Lasius flavus, Lasius fuliginosus, Formica sanguinea, Myrmica lobicornis, Tapinoma erraticum and others.[1]