Diastatidae are a family of flies in the order Diptera. They are encountered primarily in the Holarctic Region, but several species are found in the Oriental, Neotropical and Australasian regions. Members of the family number over 20 described species in three genera. There is an additional fossil genus.[1]
For terms see Morphology of Diptera
Minute flies with grey or brown-grey body and, usually, maculate wings. The postvertical bristles on head are cruciate and vibrissae are present on the head are present. The front orbital bristles are inset and upswept. The costa is interrupted near the end of Radial vein 1 and sometimes also near the humeral crossvein. The subcosta is incomplete fusing with Radial vein 1 before the apex. The posterior basal wing cell and discoidal wing cell are separate. The anal cell of wing and the anal vein of wing are both present.
Adults of living forms have been found along margins of bogs, marshes, and the edges of moist woodlands. Immature biologies are largely unknown. Hennig wrote about it thought to be Campichoeta punctum.
Diastatidae were once considered by some to be Ephydridae.
Wayne N. Mathis & David A. Barraclough Contributions to a Manual of Palaearctic Diptera. 3: 523–530. Science Herald, Budapest World Catalog and Conspectus on the Family Diastatidae (Diptera: Schizophora) Myia, 12:235–266 online here