The Anisopodidae are a small cosmopolitan family of gnat-like flies known as wood gnats or window-gnats, with 154 described extant species in 15 genera, and several described fossil taxa.

They are mostly small to medium-sized flies, except the genera Olbiogaster and Lobogaster, which are large with bizarrely spatulated abdomens.

[1] Some authors consider this group to be four distinct families – Anisopodidae, Mycetobiidae, Olbiogastridae, and Valeseguyidae.

The mesonotum is without a transverse suture; the wing is wide, with a clear anal lobe and a pattern of smaller markings (sometimes hyaline).

The subcosta (Sc) ends in the costa near the middle of wing and distal to base of Rs.

R4+5 is long, ending near tip of wing; crossvein r-m is situated near or distal to the fork of Rs.