Tselfatiiformes is an extinct order of bony fishes from the infraclass Teleostei.

[1][2][3] The order represents the most important radiation of marine teleosts during the Cretaceous period.

[1] The order appeared in the upper Albian on the coasts of Europe and North Africa and spread during the Cenomanian and Turonian on the Proto Atlantic to the coasts of northern South America, the Gulf of Mexico and into the Western Interior Seaway.

A few species still lived in the Campanian in the Gulf of Mexico and only plethodids survived until the end of Maastrichtian.

[5] More recent cladistic studies on the basis of their osteological characteristics have made it clear that they are primitive Clupeocephalans and represent the plesiomorphic sister group of a clade from Otocephala (Clupeomorpha and Ostariophysi)[6] and Euteleostei.