The Canacidae [Tethinidae were subsumed into Canacidae by McAlpine (2007)] consist of small gray acalypterate flies found in littoral habitats. About 330 extant species in some 28 genera are known from all zoogeographic regions (Pape et al., 2011).

 No described fossils have been recorded, but undetermined specimens (as “Tethinidae”) have been recorded from the Miocene amber of Chiapas, Mexico by Hurd et al. (1962) and Poinar (1992).