Class [Mammalia] Linnaeus, 1758 - mammals
   Order †Plesiadapiformes Simons & Tattersall, 1972 see Suborder Plesiadapiformes Simons & Tattersall, 1972
     Superfamily †Plesiadapoidea Trouessart, 1897
       Family †Paromomyidae Simpson, 1940
         Genus †Ignacius Matthew & Granger, 1921
           1 †Ignacius graybullianus Bown & Rose, 1976
           2 †Ignacius frugivorus (Matthew & Granger, 1921)
           3 †Ignacius fremontensis (Gazin, 1971)
           4 †Ignacius mcgrewi