Although the first genera originate in Upper Cambrian marine strata, the family becomes the most widely distributed and most species-rich trilobite family during the Ordovician.

754 species assigned to 146 genera are included in Asaphidae.

The genera of Nobiliasaphinae are distributed in tropical Gondwana and South China.

The genera of Ogygiocaridinae occur in Avalonia, Gondwana and Baltica.

Asaphidae asaphids were already fairly common during the Upper-Cambrian, when 14 genera are known from Australia, North- and South-China.