Calosargus talbragarensis new species; the first brachyceran fly from the Jurassic of Australia (Diptera, Archisargidae)

The first fly fossil discovered from the Upper Jurassic Talbragar Fish Bed in Australia is described and illustrated. Based on a single, well preserved wing, Calosargus (Calosargus) talbragarensis new species is assigned to the extinct brachyceran family Archisargidae. Wing morphology suggests a relationship between this extinct family and Stratiomyidae. The Archisargidae have so far only been found in China, Kazakhstan and Mongolia. Calosargus Mostovski, 1997 currently comprises seven species from the Callovian (late Middle Jurassic) of China and three species from the Oxfordian (early Upper Jurassic) of Kazakhstan. This oldest brachyceran fossil from Australia and first record of the Archisargidae in the southern hemisphere presents evidence that higher flies were present in this region in the Jurassic, when this group is thought to have commenced its diversification.