Larvae of 9 species are described and illustrated. They areEuryomma peregrinum(Meigen),Fannia albitarsisStein,F. canicularis(Linnaeus), and 6 unnamed species of which 5 are endemic. The larvae living in guano of the New Zealand short-tailed bat have retained a circular posterior spiracular plate with a typical cyclorrhaphous arrangement of the spiracular openings. Larvae of a subantarctic species have as many as 20 lobes on the anterior spiracle. The morphology and possible role of the paired segmental outgrowths of fanniid larvae are discussed.