Fossil Diptera cat. The family Diastatidae, treated previously by some in the Ephydridae, occurs primarily in the Holarctic Region, but several species are known from the Oriental, Neotropical, and Australasian regions as well. Adults of living forms have been found along margins of bogs, marshes, and the edges of moist woodlands.
Immature biologies are unknown.
Two fossil diastatids are known.