The fossil pupa Simulimima and the evidence it provides for the Jurassic origin of the Simuliidae (Diptera)

. Examination of the Middle Jurassic dipteran pupal fossil Simulimima grandis Kalugina shows it to possess the pupal diagnostic characters of Simuliidae and to be not significantly distinguishable from the pupa of modern Prosimulium . The nominal monotypic genus Simulimima Kalugina is assigned to that family, but provisionally maintained as valid in the absence of knowledge of associated life stages. The holotype and only specimen of S. grandis is redescribed and illustrated photographically and by line drawings, with emphasis on features which pertain to its family placement. Unambiguous assignment to Simuliidae implies an earlier Mesozoic origin for the blackflies than previously evidenced by available fossils, and it is suggested that the origins of the Simuliidae go back to Lower Jurassic times.