Phylum Brachiopoda Duméril, 1806 - brachiopods
   Subphylum Rhynchonelliformea Williams et al., 1996
     Class Rhynchonellata Williams et al., 1996
       Order †Pentamerida Schuchert & Cooper, 1931
         Suborder †Syntrophiidina Ulrich & Cooper, 1936
           Superfamily †Porambonitoidea Davidson, 1853
             1 Family †Eostrophiidae Ulrich & Cooper, 1936
             2 Family †Huenellidae Neuman, 1971
             3 Family †Syntrophiidae Schuchert, 1896
             4 Family †Tetralobulidae Ulrich & Cooper, 1936
             5 Family †Clarkellidae Schuchert & Cooper, 1931
             6 Family †Porambonitidae Ulrich & Cooper, 1936