Illustrated keys to the genera of the Eriophyoidea (Phytoptidae, Eriophyidae and Diptilomiopidae) are provided. A table comparing older and current terminology is presented. A new subfamily, Prothricinae is proposed and the tribes Colopodacini Mohanasundaram 1984 and Nothopodini Keifer 1956 are recognized. The type for the genus Trisetacus Keifer 1952 is designated to be Trisetacus ehmanni Keifer 1963. Illustrations are provided for Phytoptochetus Nalepa 1917, Aculochetus Amrine 1996 and Liroella Amrine 1996. A synopsis and alphabetical listing of genera are provided as well as references and index.